The Hidden Costs Of AI Development

Vibe coding is sold as the cheapest way to build an app. Type a prompt, watch a working interface appear, and for a few hundred dollars in credits you have something that looks like a product. For the first few weeks, that math holds up.

Then the invoice changes shape. It stops being a subscription fee and starts being a security fix, a rejected App Store submission, a developer who needs a week just to understand what the AI already built. The platform’s pricing page never mentioned any of this. It shows up later, once you try to actually ship.

The Sticker Price Isn’t The Real Price

We hear the same pattern from most founders. They spent somewhere around a thousand dollars in AI credits and put in close to a hundred hours of their own time prompting, tweaking, and testing. By that point the app does most of what it’s supposed to do, and it feels close to finished.

What they haven’t seen yet is the second invoice, the one for closing the gap between “it works when I click through it” and “it works when a stranger downloads it.” That gap is where the real costs of AI development actually live, and almost nobody prices it into the original plan. Liam Coughlin sums up the ratio bluntly. Spend a thousand dollars in credits to get an app that looks almost ready to ship, then expect to pay a developer roughly ten times that to actually close the gap.

Ten times sounds steep until you break down what it actually pays for, a developer spending the hundred-plus hours it takes to turn a working demo into something you can put in front of paying users without it falling over.

Where The Real Costs Of AI Development Hide

The costs of AI development rarely show up as one big line item. They show up as four smaller ones, and each of them tends to surprise founders in a different way.

The Audit You Didn’t Budget For

Before anyone can tell you what’s wrong with a vibe-coded app, someone has to actually read it, all of it. That work can’t be handed back to an AI, because the same tool that generates confident, plausible-looking code also generates confident, plausible-looking explanations of why that code is fine. An AI can scan a large file in about fifteen seconds. A human still needs hours to understand what it’s doing, how it talks to the database, and where it quietly breaks under real conditions. That reading time is real, it’s billable, and it’s usually the first cost founders never planned for. Our AI generated app audit checklist walks through what that kind of review actually covers, section by section.

The Security Debt Nobody Priced In

Hardcoded API keys, database credentials sitting in plain text, missing checks on who actually owns what data. These are junior-level mistakes, and AI-assisted tools make them constantly, with total confidence. Fixing them after launch costs more than building them correctly the first time would have, since someone now has to find every instance, rotate every credential, and confirm nothing was already exposed.

The App Store Rejection Loop

A subscription built on a generic web payment processor instead of StoreKit or Google Play Billing rarely gets fixed in one pass. It usually means a resubmission, a full review cycle, and often a second rejection before the app clears. Every cycle costs time, and for a startup racing toward a launch date, time is one of the most expensive things you can lose.

The Developer Hours You’ll Pay For Twice

Nothing frustrates people more than this part. You prompt the AI to fix a bug, it fixes that bug and quietly breaks two other features. You fix those, and something else shifts. Twenty prompts in, you’re paying for the same hour of work several times over, sometimes leaving the app in worse shape than where it started.

Why The Vibe Coding Cost Curve Bends Against You

Traditional software development has a fairly predictable cost curve. Effort goes in, quality comes out, and the relationship stays roughly proportional even as it flattens near the end. Vibe coding doesn’t behave that way.

“With vibe coding the curve is almost vertical. You get something working immediately, then you end up spending more time trying to finish that last stretch than you spent building the whole thing in the first place.” – Gregory Cerallo, co-founder

This is why the costs of AI development stay invisible for so long. Everything before that final stretch is fast and cheap. Everything after it is slow and expensive, and it’s the part that actually decides whether the app reaches real users. We dig into why so few vibe-coded projects clear that stretch in why most vibe coded apps never reach production.

What The Hidden Costs Actually Add Up To

It’s common to hear an app called “95% done” long before it actually is. In practice, that remaining slice turns out closer to 25 or 30% of the total effort, and it happens to be the hardest slice in the entire build. That’s security hardening, real device testing, production infrastructure, and store compliance, all landing at once. You can’t see any of that from outside the app, the same way you can’t tell whether a house’s wiring is safe just by admiring the paint job.

That’s also why nobody can give you a fixed price before opening the code. It’s custom, case by case, and there’s no way around actually going in and checking.

Paying For The Real Costs Of AI Development The Smart Way

Vibe coding still isn’t a mistake. It’s genuinely useful for validating an idea, building an investor demo, or testing whether a concept has legs. Fast and cheap, exactly as advertised, for exactly that part of the job.

“It’s very easy to start a vibe coded project. Finishing and launching it is the hard part.” – Liam Coughlin, co-founder

The smartest way to pay for the costs of AI development is to pay for them once, deliberately, through a structured audit that tells you exactly what’s salvageable and what needs work. The alternative, which is prompting your way through the last stretch one fix at a time, tends to cost more in the end and takes longer to get there.

The Real Cost Of Finishing What You Started

Vibe coding was never free. It just moved the bill to the end of the project, where it’s bigger, less predictable, and harder to plan around. Founders who understand that upfront tend to budget for it and launch on schedule. The ones who don’t usually find out the hard way, right around the point where they thought they were almost done.

Frequently Asked Questions

How much does it cost to finish a vibe-coded app?

It depends entirely on what’s inside the codebase, which is why nobody can quote a fixed price before opening it up. As a rough order of magnitude, founders who spend around a thousand dollars in AI credits and roughly a hundred hours getting an app to “looks done” should expect a developer to need a comparable number of hours, sometimes ten times the original spend, to close the remaining gap.

Why do AI-generated apps end up costing more than expected?

Because the visible 5% left to finish is rarely the actual 5% of the work. It tends to be closer to 25 or 30% of the total effort, and it covers the hardest parts of the build: security, real device testing, production infrastructure, and store compliance. None of that is visible from the outside, so it’s easy to underestimate before someone actually opens the code.

Is vibe coding actually cheaper than traditional development?

For validating an idea, building an investor demo, or testing a concept, yes, it’s fast and inexpensive. For shipping a finished, production-ready app, the comparison gets murkier once you add the cost of the audit, the security fixes, and the developer hours needed to stabilize what the AI generated.

What drives up the cost of finishing an AI-generated app the most?

The two biggest cost drivers we see are security debt, since fixing exposed credentials and broken authorization after the fact costs more than building them correctly the first time, and the “fix one thing, break another” cycle, where each AI-driven patch can undo work done a few prompts earlier.

How do you get an accurate cost estimate before committing to a fix?

Through a technical audit. Someone needs to read the codebase, understand how it’s structured, and check it against security, App Store, and production requirements before any number means anything. That’s the only way to tell what’s salvageable and what needs to be rebuilt.

Related Articles

• When To Fix vs Rebuild A Vibe Coded App
• AI Generated App Audit Checklist
• Why Most Vibe Coded Apps Never Reach Production

If your app is somewhere in that last stretch and you want a clear picture of what’s left before you spend another dollar guessing, we can help you finish and launch your vibe coded app the right way.