The Pros & Cons of Building Your Own SaaS Tools

Most of us have had this thought over the past year. Why are we paying for this tool when we could just build it ourselves? Price increases from Harvest have amplified this idea. And since the old challenges of rolling our own products don't mean months of dev time and a maintenance expense anymore, it's a little more appealing. AI coding tools can create a working internal tool in days instead of months. So what should we do? And what are we missing?

Roll Your Own or Rent It?

The build vs buy question looks a little different today. New AI coding tools help us build our own software much faster than before. And not surprisingly, more agencies are building tools they used to pay for as subscriptions.

Two things changed at the same time. Building software got cheaper. Not free, and not cheaper for every kind of need, but cheaper overall. At the same time, software subscriptions got a little riskier. Thanks for the heads up, Harvest.

Why this matters now

For twenty years, the safe choice was almost always to buy a tool instead of building it. Building cost too much. It took the team away from paying work, investing many months, and someone having to maintain it for as long as it was being used.

A subscription model turns that big cost into a predictable monthly bill. For anything that wasn't special to our business, renting made sense.

But the new AI coding tools have changed that math. Building the first working version of a tool now takes much less time than it used to. That doesn't mean building is free. Someone still has to maintain it. And the results are mixed. One study showed developers working 55% faster with AI help. Another study showed experienced developers working 19% slower, even though they believed they were faster. Put those together and I think the real lesson is: building makes sense when we need control, not because AI makes it effortless.

This year, three things changed without warning: whether a tool stays available, how much it costs, and how it connects to everything else.

What to build and what to buy

There's a simple way to think about this. Some work makes us different from other shops. Some work just keeps the lights on. The work that makes us different is worth owning. The work that doesn't should usually be a SaaS tool.

AI hasn't changed this rule so much as it's changed how affordable it is to follow. Now that building costs less, each tool deserves its own honest look. How much will it cost over time? How fast do we need it? Does it actually set us apart? Who will maintain it once it's built?

Buying a product still wins for basic needs, anything with legal requirements, or anything we need running today. Most operations tools fall here. Building those wastes our best people's time on work that doesn't differentiate us and will continue to be a time drain with maintenance.

For everything else, many agencies are landing on a middle path. Own the part of the tool that makes us different. Pay for the basic pieces underneath it. That's where tools like Operating.app with a great MCP server come into play.

None of this means we should rush out and start building everything ourselves. We definitely shouldn't. But the short list of tools worth owning is getting longer.