Whatever it is draft up a letter and send it certified mail of what the issue is and the steps they can take to resolve it.

Also, the city has some requirements from what I've heard regarding certifying certain types of rental properties so that could be another concern as a prospective owner. 

You are, sadly, going to be an expert in this are on your very first purchase, and it won't be fun. 

@Jason ReganWhile real estate agents are still key in the home buying process, buyers are increasingly looking to do more leg work online before involving the experts.

Two resident experts that own cost seg companies and work nationwide are @Yonah Weiss and @Julio Gonzalez. 

I have been to masterminds that had some of the top wholesale gurus and other guru's in them. and some of the questions these so called experts ask is really quite funny.. what they are really good at is marketing themselves and their class's..One can simply pop on E bay and look up your favorite coach there will be students who never did anything selling all their books Cds etc for 50 to 100 bucks I would go about collecting all of those first .. 

Sounds like you have an expert squatter on the property.

You'll need to get this from an agent or market expert.

After the statute of limitation expires, the lienholders cannot collect, with a few exceptions.All lienholders must send a demand letter to debtors with the intent to foreclose on the property, the demand letter must be sent by certified mail.

If you are not yet connected with an agent out there I would speak with one who is an expert in STR's that can help guide you!