I had this exact issue and hired a engineer to come look a the property. He said it was normal settling, that the previous work had fixed the issue, and that no more damage should occur (something along those lines). Anyway, 12k later I had the foundation repaired because it was shifting a lot during the seasons still. I tried to hire a lawyer to go after the engineer for the completely BS report he gave but b/c I made the mistake of having the original owner pay for the engineer report I didn't have "consideration" to recoup my losses. I couldn't go after the engineer for a wrong report that cost me 12k b/c i was too cheap to dish out the $800 and made the owner do it instead.
Either way - I got the property cheap (offered way less b/c of known issues) and ended up about even. So two points of advice:
1) Offer way less and factor in 10-20k for repairs
2) If you get an engineer report make sure you pay for it and don't try to make the owner pay instead like I did!
Hope some of that helped and good luck!