For the past year, I've been working for a company where there are a lot of extreme novice mistakes in the codebase. Even though they reviewed their code, a novice developer reviewing another novice developer aren't going to catch things that are obvious to a developer with 5+ years experience.

IMO: Target shops where they just don't have the expertise on-hand to do thorough code reviews. Don't waste time trying to convince a team full of experts with deep domain knowledge that they need you. (They probably don't.)

We also have a "problem" where there are some components that are a different language than what most of us are experts in, so they end up being developed by a solo developer. When we need to jump in, as we learn the codebase, we also see novice mistakes that are very hard to fix, because we just don't have many years of experience in that language / platform.

Thus, IMO, on your website, list out situations where shops will clearly identify a need for your service. (Team full of novices, solo developers, team members quit.) Don't go trying to convince "everyone" that they need you.