Wait, is there not lot of literature already on this topic of Build vs. Buy. Yes. There is. And we particularly like the thoughts here (How to Know When You Should Build Custom Software Over Canned Solutions by Chuck Cohn) and here (Six steps to making the right decision). Below is a quick summary in an easy to digest image from Localytics.
Not convinced? How about you try the Build Vs. Buy Calculator. Based on simple calculations, individual and small chain restaurants are better of buying small services (in this case, an inspection app that costs $50/ Month) instead of trying to build it on their own. Even with the most conservative estimates from our experience, it does not makes sense to build unless there is larger strategic value of owning the tool in-house.
Our recommendation - Go with the best of all worlds – Buy And Build. Pick and choose what to build and what to buy. It also depends a lot on the industry that you are in. What do you think? Should restaurants focus on building tools?