I hope you got a copy of her current lease agreement, you would carry over terms until it ends and then sign a new lease.. so proper notices per that lease agreement is required. 

We have a few ideas as to why they are calling, but are hoping for some fellow investor insight behind these calls and to make sure we handle properly. 

Proper screening will almost always help you avoid a bad egg in the first place but bad eggs do occasionally slip through. 

I recently decided I would sell it, found a buyer but cannot get title insurance because the the county law office did not properly notify the heirs.

I also don't know if he's the guy I want coming back to fix it, since it clearly wasn't installed properly.

I would like to turn this into a great success story of how I got started investing in apartments and I believe I can make it happen with the proper guidance.

So until you list or need to refinance I'd be satisfied that you more than likely increased value and when you market for rent go out and look at similar size apartments in your area so you are in line with proper rents for your market. 

proper installation?

Anyway- you will always get the home with a proper eviction.

Cash is king and you might be able to build with out following the proper guidelines, but buyers will have trouble with financing like FHA when you try to sell.