Inherited a Half-Built Unity Game? What a Code Audit Checks and What It Costs

If nobody can produce a working build from the files you have, get an audit before anyone writes new code. Features added to a project nobody understands tend to break things that already worked.

You’re probably in this situation if a few of these sound familiar:

• Your developer has left, or it takes a week to answer an email.
• You got a zip file or a folder, not access to a Git repository.
• Unity asks to upgrade the project, or shows errors as soon as it opens.
• Nobody can put a build on your phone today.
• You’ve had quotes for finishing the same game that are months apart.
• The last build was made before this year’s Apple and Google changes (more on those below).

If two or more of these apply, an audit costs less than finding out halfway through the next contract.

An audit tells you whether a new team can open your project, build it, and change it without breaking things. It’s part codebase review and part build test, and it covers six areas.

The first step is the dullest one: opening the project in the exact Unity version it was last saved in, which is written in ProjectSettings/ProjectVersion.txt. Opening it in a newer version first, as Dana did, starts an upgrade that can hide the very problems you’re looking for.

Version support matters too. Unity’s release page lists Unity 6.3 LTS as supported until December 2027, while support for Unity 6.0 LTS ends in October 2026. On anything older than 6.3, the audit should say whether to upgrade now or later, since an upgrade is a small project of its own.

A messy folder structure isn’t fatal, but it slows every later task (here’s what a well-organized Unity project looks like). The engineer will also note the render pipeline, since changing it late means reworking materials and lighting. See how URP, HDRP and the Built-in pipeline compare.

Four problems are worth checking for first: missing files, builds that no longer meet store rules, no change history, and accounts registered to someone else. Found early, they go into the estimate instead of turning up halfway through the work.

Missing files and broken references

Unity tracks how assets connect through small .meta files that sit next to every asset. They’re easy to lose when someone copies only part of the Assets folder, or a repository is set up to ignore them. Then references break, and you’ll see “Missing Script” warnings on objects, and materials that show up bright pink, which usually points to a shader or render pipeline problem.

Paid plugins bought on the previous developer’s Asset Store account are tied to that account. Unity only transfers them in limited cases through its support team, so you may need to buy them again under yours.

Builds that no longer pass store rules

A game that built fine last year might be blocked from the stores today because Apple and Google raise their minimum requirements every year.

• Google Play: Since August 31, 2026, every new app and every update must target Android 16 (API level 36). Games already on the store that target Android 14 or lower are also hidden from new players whose phones run a newer Android version.
• Apple: Since April 28, 2026, every upload to App Store Connect must be built with the iOS 26 SDK or later, which comes with Xcode 26.

Neither rule switches off a game players already have installed. What they block is your next update, and on Google Play, new installs on newer phones. An old Unity version or outdated ad and payment plugins are common reasons a project can’t meet them.

No version control

A lot of small teams never set up Git or Unity Version Control, or the developer set it up in their own account and kept it when they left. Without that history, nobody can see what changed or roll back a change that broke something. Our guide to Git in game development explains why it matters.

Accounts and services you don’t control

Founders are often caught off guard by this one. The game’s backend, its ad network account, or its analytics project may be registered to the previous team. The audit should list every outside service the game talks to and whose name it’s in.

You should get a ranked list of problems, a plan for fixing them, and a recommendation on whether to repair or rebuild. In short, the report should tell you what to do next.

A risk list

Each problem, where it sits in the project, how badly it blocks launch, and what happens if you leave it. The list should also say whether the game builds for each platform you care about and who owns each plugin and outside account.

A fix plan

The order to work in, with a rough size for each item. It usually starts with a clean, repeatable build, then whatever the stores require, then bugs, and then the features that were never finished.

A repair-or-rebuild call

This is the part that decides most of your budget.

Don’t read too much into a broken build on its own. A project that won’t build today might be one missing package or a version mismatch away from working. The call should weigh everything together, especially what fixing the core systems would cost compared with rebuilding them.

An audit also has limits. It isn’t a full QA pass or a security audit; it won’t tell you whether the game is fun, and it doesn’t promise the game is ready to launch.

It depends mostly on how big the project is and whether it builds at all. Most audits are priced on senior engineering days, often as a fixed fee agreed before work starts. The ranges below are based on prices game studios and code audit firms published in 2026.

Treat these as market benchmarks, not quotes. Be wary of 150–500 “code reviews” on freelance marketplaces: they’re usually a one- or two-hour skim for obvious red flags, not an audit. Some studios also credit the audit fee against the fix work if you hire them for it, so it’s worth asking.

Expect it to take longer if the project won’t build on day one, ships on several platforms, has multiplayer or its own backend, or arrives with no documentation and no history.

Once you know what needs doing, our breakdown of Unity game development cost and our guide to how long it takes to develop a video game will help you sanity-check the quotes for finishing it.

Before a new team can take over a Unity project, you need everything it takes to build, sign, and publish the game without the old team. Ask for these in writing:

1. The full project: repository access with its history, or a complete copy that includes the Assets, Packages, and ProjectSettings folders. The Library folder isn’t needed, because Unity rebuilds it.
2. The Unity version the project was last opened in.
3. Your Apple Developer and Google Play Console accounts, registered in your name or your company’s.
4. Signing keys and their passwords, meaning the Android keystore and the Apple certificates. Losing the Android key can make updating your existing store listing much harder.
5. Logins for every outside service the game uses, such as the backend, Unity services, analytics, ads, and payments.
6. A list of paid plugins and whose account bought each one.
7. Original art files, design documents, and any notes on how the systems work.

If your contract never said who owns the code and the accounts, sort that out before the next team starts. Our guide to protecting your IP in outsourced game development covers what to get in writing.

With the report in hand, every team can quote against the same facts. The next step is a fix-and-finish estimate built on what the audit found.

At Juego, the audit report is where that estimate starts. If you want one team to carry the project from audit to launch, our Unity game development company page shows how our engineering, art, and QA teams work on Unity projects together. If the report says you’d be better off starting again, or you only need a little help, we’ll say so.

Whoever you go with, ask how they’ll test the game, because inherited code tends to hide bugs (this overview of types of game testing helps). Our list of common mistakes when choosing Unity developers can help the next handover go better than the last, and our practical guide to Unity game development covers the bigger picture.