If you are worried about this there are companies that handle servicing these payments automatically on a scheduling system if you have a bunch of them. 

and I think there are several remedies to resolve this - and the developer and the city's business/permitting services both have liability here. 

Unless you're financially prepared to deal with these issues and accept that 'once you know, you must always disclose' defects, I would move on to finding what is truly a good deal - as a good deal is only as good as its bones.  

The owner is a former mortgage underwriter and she is preparing documents herself and having her friend at a title company execute the sale.  

Preparing my for next purchase.

Even if you are exempt, I suggest you use a loan servicer!

I researched some eviction attorneys and property management companies who offer 'problem tenant' services so most likely will reach out to them.

I attended an informational training for beyond bnb, without signing up for their service, I implemented a couple strategies they discussed and found they worked.  

Sometimes I see properties currently for rent lower than those 3 services. 

Out of all of those listing services, do you have luck with one more than another?