Prevention is always less costly than remediation.

I issued them $200 fines for each lease violation and gave them 24 hours to remedy according to the lease.

He has been paid $7000 for demo, new roof, and putting up drywall as well as mold/ water remediation.

This is also on the builder as well in many cases when they do not remedy permitting delays in a timely manner. 

If you truly distrust the seller, make you have the property inspected again after the repairs/remediation is done and you and your agent can take it from there.

Some of those guys deal with that stuff all of the time and could probably offer you some ideas for remediation. 

Some potential issues that come to mind are mold and radon, but I could test for both of these and potentially remedy.

Is there any remedy if he was caught in the fraud mortgages?

---------------------------------------------------------------------------------------Sure wish that some workable remedy against this virus is created, & the sooner the better.

These items seem small, but can really add up, especially if you have a leak and need to do mold remediation, drywall repair (or, worse, if it gets into the foundation), painting, and floor repair.