Invisory Limited is the consultancy practice of Mark Barber; I work with owners, management teams and investors on acquisitions, disposals, new markets and changes of direction. Projects are few, and each one is scoped to a single question. Most of my experience is in ICT and technical services, where I have operated, acquired and exited businesses – so I have made these decisions as well as advised on them.
Owner-managed and private-equity-backed SMEs, typically £1m–£50m of revenue.
This is the size of business where the decisions are large relative to the balance sheet and there is no in-house strategy function to lean on. Below £1m the questions are about survival rather than direction; above £50m there is usually a corporate development team already in place. In between sits a band of companies making consequential choices – whether to sell, what to buy, which market to enter – with management time that is already fully committed.
That is the gap Invisory fills: the analysis and the second opinion a larger business would have in-house, bought for the length of a single question or project, rather than retained permanently.
Most of that work has been in ICT and technical services, sold to enterprise and public-sector customers. It is the sector I know from the inside, so I am useful on the detail as well as the structure: what a recurring revenue line is worth, which accreditations gate which customers, and why two businesses with the same profit are not worth the same money.
Where I take a chair or non-executive role, I am open to discussing investment alongside it. Usually at the size described above, occasionally smaller. By introduction, and only where I have the experience to add something.
Services
Grouped by the decision they support. Most engagements use one or two of these.
Seven deliverables from two engagements: a buy-and-build programme in a B2B technical services sector, prepared for the board and its investor; and a market entry study for a new entrant. Client names, sector detail and all figures have been changed; the structure, method and depth are as delivered.
Selected work · scroll for more →
Market sizing
TAM
SAM
SOM
V1V2V3V4V5V6
Report · 50 slides
Market & competition analysis
A six-part market study sizing the opportunity from the total addressable market (TAM) down to a defensible serviceable obtainable market (SOM), then testing how winnable it is. The central finding was a two-speed market: broadly flat total spend concealing a specialist layer growing at three times the rate. It is structured in six parts: market size by vertical and service line; growth; competitive intensity on Porter’s five forces and positioning on his generic strategies; routes to market and the qualifications that gate them; consolidation dynamics; and the buying population. It closes on how customers perceive a private-equity-backed supplier, and how to manage that.
Value bridge
+
=
PlatformBolt-onsGroupentryexit
EBITDA build (£m) × exit multiple (×)
Report · 20 slides
Investment thesis
The value-creation case, built on two levers that multiply rather than add: earnings growth through a qualified acquisition pipeline, and multiple expansion from buying sub-scale assets and exiting a scaled, capability-complete group. The work traced the EBITDA bridge acquisition by acquisition, set capability multiples against precedent transactions, then adjusted for scale and revenue mix to reach a blended exit multiple. It closed on hold-period and leverage sensitivities, the best public–private revenue mix, the highest-value capability gaps, and a risk register with mitigations.
Scenario toggles
TargetEBITDAMult.EV
3 deals£20m13.6×£272m
5 deals£25m14.0×£350m
8 deals£30m14.3×£429m
Full build£34m14.5×£493m
Model · 5 linked sheets
Exit scenario model
A live workbook sitting under both reports, built so the board could test the plan rather than read a fixed answer. Every acquisition target carries an on/off toggle; switching one changes the consolidated capability map, the revenue split by vertical, the public–private mix, the blended exit multiple, enterprise value and the return sensitivities together. A scenario explorer answers the two questions that matter: how few acquisitions it takes to reach a target, and how high a multiple is achievable near it. Both come from an exhaustive search across every possible combination of targets. Each figure reconciles to its source, and every assumption is written down.
Ask once, in order
Gate 1
Written pack
24 items
→
Gate 2
Management agenda
9 sections
→
Gate 3
Investor list
19 items
answered once, carried forward
14 of 19 items link back to an earlier gate
Template · 3 gates, 8 sheets
Staged diligence request
A request list built in three gates, so the company is never asked the same question twice. Gate 1 is a written pack answered from existing management information. A green light leads to a face-to-face agenda in which each functional lead owns a section. A second green opens the investor’s financial request list, which fills in anything already answered and asks only for what is new: 14 of its 19 items link back. One build produces an internal copy, carrying the synergy workings, and a clean external copy for issue.
Scored against the plan
Gap fill20%5
Earnings20%4
Returns20%4
Price20%3
Mix10%4
Concentration10%2
target plan
Weighted score 3.8 · Proceed, with conditions
IC paper · 15 slides
Acquisition assessment
An investment committee paper on a proposed bolt-on, written for the board, the investor and its limited partners. The target was scored against the group’s own plan rather than in isolation: earnings and margin, returns, customer concentration, public–private mix, the service gaps it would fill, and price against precedent transactions. The scorecard put the decision on a page; the model showed what it did to the group. Switching the target into the exit scenario model updated the capability map, the blended multiple and the returns together, so the committee could see the accretion rather than be told about it.
Target selector
TargetIncOwnerIM
Target AONthis✓
Target BONthis·
Target CONnext·
Target DOFF–·
Target EONnext·
Target FOFF–·
c.20 targets · six pillars · c.100 service lines
Model · 7 linked sheets
Capability map & pipeline workbook
Built to answer one question for each target: what does it add that the group does not already do? The starting point was a clean platform of just under 100 service lines, sorted into six industry-standard pillars. Each of around 20 targets carries an on/off switch and a flag for whether its information memorandum has been analysed. A second marker says whether this owner buys it or it is left for the next one. The same switches drive the revenue split and the exit model, so the capability case and the valuation case cannot drift apart.
Where to play · nine-box
Attractiveness
Ability to win20 placed
Three sit top right · attractive and winnable
Report · 41 slides
Market entry study
A study of a UK B2B services supply chain, testing how a new entrant could get in and win. It sized the supplier-addressable market as a range, with the method shown, then mapped which buyer controls each line. The central finding was that most of the spend never reaches an open market: two of the three buyers appoint a single supplier for the year, and only one line is tendered. Entry became an acquisition question rather than a marketing one. Screening 350 candidates against filed accounts and ownership registers left 20 genuinely independent businesses, placed on a GE–McKinsey nine-box of attractiveness against ability to win.
A point flagged as unresolved is worth more than a confident answer that does not survive the meeting.
Approach
01
Senior throughout
You work with the person who scoped the project, from the first conversation through to the final report. I do not delegate to a team you have never met. That means the question asked in week one is informed by the same judgement that writes the conclusion, and you can pick up the phone to the person who formed it.
02
Scoped to the question
Some decisions need a full diligence exercise with a data room, management interviews and a modelled range of outcomes. Others need a day or two, a week or a month; they all need a straight answer. I size the work to the decision, not to a standard template, so you are not paying for analysis that will never change what you do next.
03
Written to be used
I write for boards and investment committees: the analysis up front, the reasoning laid out plainly, and the evidence where it can be challenged. A straw man goes up early – a first view, deliberately rough, for you to attack – and the report is what survives it. What arrives is a written report, and a working model where the question needs one.
04
Where AI fits
I use AI tools for research, for organising large volumes of material, and for building and checking documents and models. They are not used to decide the answer. Every figure traces back to a named source, the conclusions are mine, and I sign off everything before it is sent. Client material is used only under business terms that prevent it being used to train a model.
Background
Mark Barber Founder & Principal
I have spent my career in and around technical services businesses – operating them, growing them and exiting them – and have sat on both sides of a diligence process.
My career began in mechanical and production engineering, in a role spanning the UK and international markets, before I joined a diversified group formed from my family’s engineering business. There I worked on a range of corporate development projects as part of a buy-and-build strategy.
More recently I worked as a freelance business development consultant to a small private equity house, across several of its portfolio companies, before undertaking a management buy-out of one of those businesses, which I then operated and exited in 2022. Since then, I have worked in a board advisory role, developing and refining a buy-and-build strategy for a group of businesses in which I remain an investor.
Invisory Limited was set up to offer that experience to other business owners and investors. Most of the work is either commercial due diligence and market analysis for an investor, or the same discipline turned inward for an owner deciding whether, when and to whom to sell. I usually work alone, and bring in specialists where a project needs them. The name is a contraction of investment and advisory.
Short notes on strategy, transactions and the markets I work in, plus the occasional side project.
Use the contact form to discuss a particular requirement.
Notes · scroll for more →
Oct 2026Invisory
Question → tool
Worth being in?Five forces
Where is growth?Ansoff matrix
What are we?SWOT
So what do we do?TOWS
Diagnose, then prescribe
Method · SWOT, Ansoff, TOWS
A strategy framework earns its slide only if it changes the decision
Strategy decks carry a SWOT and a five forces analysis because decks are expected to. My test: if removing a framework would not change what the board decides, it goes in the appendix. The ones that stay come in pairs. Five forces says whether a market is worth being in; an Ansoff matrix says how much of the growth plan sits in the riskier quadrants. A SWOT is a diagnosis; a TOWS is its prescription.
Oct 2026Invisory
Sensitivity
Exit mult.
Growth
Margin
Deal size
Change in equity value, one input at a time
Method · tornado sensitivity
Find the assumption doing the most work
Every plan rests on a handful of assumptions, and one usually carries more weight than the rest. A tornado chart finds it: move each input by a plausible amount, one at a time, and rank them by how far the answer moves. In a buy-and-build it is often the exit multiple, not anything management controls month to month. That turns the question from whether the budget will be hit into what would make a buyer pay more.
Oct 2026Invisory
Information schedule
Revenue by serviceE · Wk 1
Win / loss recordE · Wk 1
Pipeline by stageE · Wk 2
Customer feedbackD · Wk 2
Appended to the statement of work
Practice · scoping up front
Agree the information before the fee
Most overruns start in week one, when data everyone assumed existed turns out not to. Each statement of work now carries a schedule of what is needed, in what form, from whom and by when, each marked essential or desirable. Essential items gate the sections that depend on them; for the rest I use public evidence and say so. It is a dull page, and it is why a fixed fee stays fixed.
Oct 2026Invisory
Ownership screen
Members screened
350
Ownership-checked
55
Genuinely private
20
File turnover
6
Size the other 14 another way
Method · 350 screened to 20
Ranking a market where most companies do not publish turnover
A screen of a UK services sector began with 350 trade-association members and ended with 20 independently owned businesses. Well-known names fell out once the ownership chain was followed to the top, held by listed groups or private equity. Of the 20, only six disclose turnover. Headcount and net assets from the same filings rank the rest honestly; an estimate dressed up as a number would not.
Oct 2026Invisory
Equipment rental margin
Gross margin
~60%
Operating margin
~2%
The gap is kit sitting idle
Analysis · utilisation first
A 60% gross margin is not a 60% business
Equipment rental looks like the best line in the sector: one independent rental company filed a gross margin of almost 60%, against an operating margin of about 2%. The difference is kit bought for four busy months and idle for the rest, with the people and warehouses kept ready for it. Another rental company went into administration with heavy debt and a store of unused kit. In an asset-backed deal, utilisation is the first number to ask for.
Aug 2026
Invisory
Growth by layer
Growing half +10%
Flat half 0%
Yr 1Yr 3Yr 5
Headline +5% · true of neither half
Sizing · split before averaging
The average of two markets is a market nobody sells into
Picture a market growing at 5% a year. Split it, and it is often two markets: one half flat, the other growing at 10%. The 5% describes neither, and every part of a plan that matters depends on which half you are in. Sizing the part of the market you actually sell into is duller work than quoting the headline, and it usually changes the answer.
Jul 2026
Invisory
Multiple by capability
Spec.
14×
Cloud
11×
Managed
9×
Resale
5×
Same £1m EBITDA, three times the value
Valuation · sequencing first
Not all earnings are valued equally
A pound of specialist, accredited EBITDA is worth roughly three times a pound of resale EBITDA at exit. In a buy-and-build that makes sequencing a valuation decision, not a scheduling one: what you acquire first sets the multiple the rest of the group gets measured on.
Jun 2026
Invisory
Assumption panel
Target CON
Target DOFF
Hold period5 yrs
Exit EV£350m
Recalculates live in the meeting
Practice · a model to test
Build the model so the board can argue with it
Hand a board a single number and they spend the meeting deciding whether to trust you. Hand them a model where they can switch a target off and watch the exit value move, and they spend it deciding what to do. Same analysis, entirely different conversation.
Exploration stocks trade on a story, so the story and the numbers belong side by side. Minotaur follows 19 gold, silver, copper and rare-earth explorers and developers listed in Sydney and Toronto. Each carries a stage bar from start-up through feasibility to production, market value against the latest study NPV (net present value), and the share price that NPV implies. Alongside sit broker targets, the next milestones, how the work is being funded, the project pinned on a map and a live 12-month chart. The list is screened on written rules, set out in the app, and the data refreshes itself each week. Add a holding and its average cost to keep a running P&L.
A companion for a day at the races, UK and Irish, Flat and Jumps. Each meeting has the card with every runner’s silks drawn from the owner’s registered colours, a plan of the course showing the start, the route and each fence or hurdle, and the going alongside a live weather forecast. Every runner gets a win and a place chance – the bookmakers’ margin stripped out of the prices, then adjusted for form, rating, going, course and distance, and the jockey and trainer – and every race gets a confidence score. A results page keeps the model honest: predictions are frozen before the off, so the strike rate, the calibration against the market and the profit or loss at starting price cannot be tidied up afterwards.
Shore bass reward timing more than tackle. Choose a mark, a date and a start time, and BassMax works out the tide from the sun, the moon and the national tide-gauge constants, sets it against first and last light, pulls in the forecast, and scores every 10 minutes either side of your start. It then suggests the lure, colour, weight and leader, and marks where to stand as the tide floods and ebbs. Forty-six UK marks are built in; anywhere else is found by name and read off the coastline. It began as a way to plan neap sessions on the upper Severn.
Opens in a new tab · tide times are estimates, so check EasyTide · the offline copy runs without internet; the forecast and place search need a connection
School fees, a house sale, the start of drawdown, gifting, inheritance tax and an assumed first death, sequenced in the order they actually land – then run 10,000 times. It outgrew the spreadsheet, so it became a small web app called Buoyant: move an event and watch the whole distribution shift. The output is not a number but a percentage – in how many of those futures the money lasts – which is of more use than one confident forecast and is easier to sanity-check.
Opens in a new tab · illustrative figures only · the offline copy runs with no internet
May 2026
Side project
Itinerary · Japan
Tokyo4nair
Sapporo3nair
Kyoto4nrail
Fukuoka3nrail
18 legs · 7 bases · 3 flights
Three weeks in Japan, planned on one sheet
Eighteen legs, seven bases, six Shinkansen routes and three flights, from Tokyo up to Sapporo and back down through Kyoto, Hiroshima and Fukuoka. Every hotel and train sat in one sheet with its cost, status and a rating, which meant a change on day four could be traced through everything downstream in about a minute. Most of the discipline transfers. The bit that does not: nobody thanks you for a critical path on holiday.
Apr 2026
Side project
Resort scorecard
VillChamMorg
Transfer1h502h052h15
Base alt.1300m1050m1350m
Linked km130580580
£/m²9.4k11.2k7.1k
Ranked on criteria set before viewing
Choosing between three Alpine valleys
Villars, Champéry and Morgins, compared on transfer time, base altitude, lift links, running costs and how easily you get your money back out. Writing the criteria down before looking at any particulars was uncomfortable, and it reversed the answer twice. Recommended, in property as much as in deals.
Mar 2026
Side project
Scoring, end on
6
1
1
behindgoalbehind
18 a side · 4 quarters · no offside
Australian Rules, explained in one page
Eighteen players a side on an oval, four quarters, and a scoring system that rewards precision: six points through the middle posts, one if you miss into the outer channel or a defender gets a touch. You can run with the ball but must bounce it every 15 metres; you can kick or handball but never throw; catch a kick that has travelled 15 metres and you have earned a free one. There is no offside, so nothing resets and nobody holds a line; the whole ground is live, all game. Tackle between the shoulders and the knees, and only when the man has the ball.
