Equity-for-Build Deals: When They Pay Off, When They Wreck You

Every agency founder gets the email. A charming pre-seed founder, a deck with a hockey stick, and the line: "We're a bit cash-light right now — could you do this for some equity?" The honest answer is almost always no. But not always. Here's how we actually decide, and the deals we wish we'd structured differently.

Why agencies keep saying yes to bad equity deals

The pitch is intoxicating. You're already going to build the thing. The client says they're going to be the next category leader. Trading 200 hours of engineering time for 4% of a rocket ship sounds like a smarter trade than invoicing £30k and watching it disappear into payroll.

The problem is the base rates. Most pre-seed startups don't return capital. Of the ones that do, most return a small multiple. Of the small fraction that exit big, your equity is usually diluted into irrelevance by the time anything meaningful happens. You are not Sequoia. You don't get pro-rata. You don't pick the board. You're a service provider with a paper certificate.

That doesn't mean every equity deal is a trap. It means the deal has to be structured like you're a real investor, because functionally you are — except your capital is your team's time, which is the most expensive and least replaceable thing you own.

The math we run before any conversation about percentages

Before we discuss equity, we calculate two numbers and stare at them.

Opportunity cost. What would those engineering hours have earned on a normal contract? Not your blended rate — your marginal rate, because equity work usually crowds out billable work. If we'd staff three engineers for three months, that's roughly £180k–£240k of foregone revenue at typical mid-market rates. That's the cheque the founder is actually asking you to write.

Required outcome. Given the opportunity cost, what does the company need to be worth at exit for our equity to be a good investment — not break-even, but better than the alternatives? A reasonable hurdle for risk-adjusted returns on this kind of bet is 5x–10x your opportunity cost over five to seven years, because you're underwriting a high probability of zero.

Here's the rough version we sketch on a whiteboard:

opportunity_cost     = hours * marginal_rate
required_return      = opportunity_cost * 10        # hurdle multiple
your_final_equity    = initial_equity * (1 - expected_dilution)
required_exit_value  = required_return / your_final_equity

# Example
# 1,200 hours * £180/hr = £216,000 opportunity cost
# Hurdle: £2.16m return needed
# 5% initial equity, 70% dilution over 4 rounds -> 1.5% final
# Required exit: £144m

If the founder can't make a credible case that the company will be worth more than the required exit value, the equity portion is a gift, not an investment. That's fine — just price it as a gift and decide whether you want to give it.

The dilution trap nobody explains

Founders pitching equity-for-services often quote you a percentage of the current cap table. That number is fiction the moment they raise. A 5% stake before a seed, Series A, and Series B can easily become 1.2% — and that's if nothing goes sideways with option pool refreshes, bridge rounds, or down rounds. Anti-dilution protection is for institutional investors, not for the agency that built the MVP.

If you're going to take equity, model the dilution. Assume worse than the founder claims.

When equity actually makes sense

There are three scenarios where we've taken equity and not regretted it.

The repeat operator. The founder has done this before, ideally with an exit. They're not asking because they're broke; they're asking because they want aligned partners and they're being efficient with capital. These deals usually come with cash too — and the cash portion alone covers your costs.

The strategic adjacency. The product they're building is so close to your firm's positioning that the work itself is marketing. You'd build a similar reference project anyway. The equity is a bonus on top of a project you'd subsidise for the case study.

The convertible structure. Instead of straight equity, you take a SAFE or convertible note for the value of your work, with a discount and a cap. You get investor-class instruments, not founder-class scraps. When the priced round comes, you convert on better terms than the people who sent wire transfers later.

Notice what isn't on this list: "the idea is amazing." Ideas are cheap. We've passed on brilliant ideas attached to first-time founders with no domain expertise and no money, and we've taken equity in objectively boring B2B tools run by people who'd already shipped twice.

Contract terms we won't sign without

If we do an equity deal, the paperwork looks nothing like a normal SOW. The terms below aren't aggressive — they're the bare minimum to keep you from being the dumbest money on the cap table.

• A cash floor. We will not work for pure equity. There's always a cash component covering at least direct costs (salaries, infra, taxes). Equity is upside on top of break-even, never instead of survival.
• Information rights. You get the same quarterly updates and cap table access as preferred investors. If they won't grant this, they're planning to keep you in the dark.
• Pro-rata participation. The right (not obligation) to invest cash in future rounds to maintain your percentage. Without this, you will be diluted into nothing.
• Tag-along rights. If founders sell their shares, you get to sell yours on the same terms. Stops a secondary sale leaving you holding common stock in a company that's now run by someone else.
• Most-favoured-nation clause. If they give a later service provider better terms, you get matched. You'd be amazed how often this triggers.
• Scope lock with a real change-order process. Equity makes founders feel entitled to infinite scope. The contract has to make it explicit: equity buys this build, not a permanent CTO.

We also include a buyback clause for the first 24 months. If the relationship sours or the founder pivots into something we don't want to be associated with, they can buy our equity back at a pre-agreed multiple of the cash-equivalent value. It's saved us twice.

What we put in the SOW itself

The statement of work for an equity-inclusive engagement is stricter than a fixed-price one, not looser. Specifically:

• An explicit cut-off date. Equity portions of the contract terminate on a calendar date, not on "launch." Founders will redefine launch forever.
• A defined deliverable list with acceptance criteria. Same as any fixed-bid.
• Named team members and a maximum hours-per-week ceiling. This prevents the slow expansion into being their unpaid engineering department.
• Clear IP assignment that activates on equity issuance, not before. If the shares don't get issued on schedule, the IP stays with you. This concentrates the founder's mind wonderfully.

If you want a deeper look at how we handle scope on fixed-bid work, our services page has more, and we've written about scope conversations on the blog before.

The cultural cost nobody puts on the spreadsheet

Even a well-structured equity deal has a tax on the team. Engineers can tell when a project is "the equity client" — the priority is fuzzy, the deadlines are stretchier, the feedback loop is slower because the founder is also fundraising and pitching and probably building deck slides at 1am. The work feels different, and not in a good way.

If you take more than one or two equity deals at once, the agency starts to feel like an unfunded startup studio. Utilisation drops, cash flow tightens, and senior engineers — the ones who can do this work — quietly start interviewing because they want to ship things that matter to paying customers.

We cap equity engagements at one active deal at any time, and never more than 15% of engineering capacity. That ceiling is non-negotiable internally.

When to walk away mid-deal

Sometimes the deal is good on paper and bad in practice. Signs to cut your losses:

• The founder misses two consecutive board updates or won't share the cap table after signing.
• They raise a round and the new lead requires you to convert your equity to common at a haircut. Push back, hard.
• Scope creep crosses 20% of original estimate within the first quarter — they're treating you as employees, not investors.
• They hire an in-house team and quietly stop returning your calls. You're being phased out before vesting completes.

Having an exit clause matters. Negotiate it when everyone still likes each other.

Where we'd start

If you've never done an equity deal and one is on the table, do this first: write down the cheque size you would have to be paid in cash to be indifferent between the equity and the cash. Then ask yourself if you'd actually wire that amount of your own money into this company at this valuation, sight unseen. If the answer is no, you've already decided. Take the cash work, or take a smaller piece of the project with a real budget, and let someone else fund the founder's dream with their balance sheet.

The agencies that get rich on equity aren't the ones who say yes a lot. They're the ones who say yes once every few years, and structure the deal like grown-ups when they do.