What should you check before buying a side project or online business?

Work through five areas: the money (revenue verified at the payment processor, the trend, and churn), the audience (where traffic and customers come from and whether it's diversified), the product (the codebase, dependencies, documentation, and any committed secrets), transferability (whether ownership, domains, and accounts can move cleanly), and the legal side (IP ownership, licenses, and borrowed assets). Finish by reading the seller — why they're selling and how straight they answer. Then transact through escrow.

How do you verify a project's revenue before buying?

Never trust a screenshot. Ask for read access to the payment processor (Stripe, the app store, or similar) and reconcile it against bank statements and the seller's profit-and-loss. Look at the trend over the last several months, not just a trailing average, and separate recurring revenue from one-time spikes. Verifiable revenue is the single most important thing you confirm.

What are the biggest risks when buying a side project?

Four recurring ones: revenue or traffic you can't independently verify, ownership that won't transfer cleanly (platform or account lock-in), legal or IP landmines like committed API keys or borrowed assets, and a business that only works because the founder runs it. A good checklist surfaces all four before money changes hands.

The Due Diligence Checklist for Buying a Side Project (2026)

Buying someone's side project is thrilling right up until the moment you realize the revenue was screenshots, the traffic came from one thread that already died, or the whole thing lives on an account that can't actually be transferred to you. Diligence isn't paranoia — it's the difference between buying an asset and buying a story. Work these five areas before any money moves, and you'll know exactly what you're getting.

Area 1The money

Start here, because everything else is a footnote if the revenue isn't real.

Verify revenue at the sourceNot a screenshot — read access to the payment processor (Stripe, the app store, PayPal). Reconcile it against bank statements and the seller's profit-and-loss. Direct verification is the gold standard; brokers won't list without it.

Read the trend, not the averageA trailing-twelve-month average hides a decline. Look at the last several months against the prior year — is it growing, flat, or quietly sliding?

Separate recurring from one-offA subscription dollar is worth more than a one-time-spike dollar. Understand churn, and be skeptical of a big month that came from a single launch or viral post.

Total the real costsHosting, APIs, subscriptions, ad spend. "Revenue" isn't profit until you subtract what it takes to keep the lights on.

Area 2The audience

Revenue comes from somewhere. Find out where — and how fragile that somewhere is.

Confirm where traffic and customers come fromGet read access to the analytics. One search keyword, one platform, or one influencer is concentration risk you're inheriting.

Check diversification and durabilityTwo stable channels beat one great one. Aged, organic traffic is worth more than something one algorithm update from zero.

Understand what keeps usersIs there a reason people stay — data, habit, a network — or would they churn the moment a shinier option appears?

Area 3The product & code

For a software buy, the code is the asset. Don't buy a black box.

Inspect the codebase (or have it analyzed)Tech stack, structure, dependencies, documentation, tests. Is it something you — or someone you can hire — can actually maintain? On Vertos, a free AI analysis verifies the real code on every listing so you're not guessing.

Check for committed secrets and shortcutsAPI keys in the repo, hard-coded credentials, no error handling — these are both a security risk and a tell about how carefully it was built.

Confirm it's genuinely built, not a thin wrapperIf it's "AI-powered," make sure there's real product under the label — a workflow, data, retention — not just a prompt and a Stripe button.

Area 4Transferability

The quiet deal-killer: an asset that can't actually become yours.

Confirm every account and domain can moveDomain, hosting, the no-code platform, third-party services, app-store listings. Know exactly how each one transfers to a new owner before you pay.

Ask what depends on the founderUndocumented routines, personal relationships, a manual weekly script. If it only runs because they run it, you're buying a job, not a business.

Get the handoff in writingA list of exactly what transfers and a short transition-support window. Vague handoffs are where deals fall apart after the money's gone.

Area 5Legal, risk & the seller

Last, the landmines — and the person on the other side.

Clear the IP and licensingDoes the seller actually own it? Check for borrowed code, unlicensed assets, trademark conflicts, and that any open-source licenses allow commercial use.

Ask why they're selling — and weigh the answer"Moving on to a new project" is normal. Evasiveness, a rush, or a story that keeps changing is not. How straight they answer is data.

Transact through escrow — alwaysOnce you're satisfied, never send money directly. Escrow holds the funds until the assets actually transfer, so you can't pay for something that then evaporates.

Diligence isn't about catching a liar. It's about turning everything you'd otherwise take on faith into something you've actually seen.

The bottom lineBuy what you verified, not what you were told

You don't need a perfect project — every small acquisition has a wrinkle or two. You need to know the wrinkles before you pay, so you can price them in or walk away clear-eyed. Run the five areas, get everything you can't see put in front of you, and settle through escrow. Do that and buying a side project stops being a gamble and starts being what it should be: a running head start you got for a fair price.

Buy with the guessing removed.

Every Vertos listing comes with a free AI code analysis, and every deal settles through Stripe escrow — so your diligence starts from facts, not screenshots.

Browse projects →

Check everything. Assume nothing. Then buy with confidence.
— The Vertos team

Sources & notes

Diligence practices reflect how established marketplaces and brokers vet listings. Verification & vetting standards: Empire Flippers and FE International. General education for buyers, not legal or financial advice — for a large purchase, involve a professional.