I imagine the process is like any acquisition. From what I've seen so far, basic things people look for:
1. Business Registration (LLC, B corp, C corp, etc)
2. PnL for past 5 years
3. Tax statements
4. Banking statements
5. Inspect codebase, database, and cloud infra.
Also I'm surprised that you'd ask it here. Considering you're about to drop $250k, I imagine you'd hire a lawyer to look over everything.