In my market, you can request to push back closing.

If you like one of their offers, the mortgage loan officer will request income documents, and then pass you on to the mortgage processing team3.

Maybe you can sue them.To be honest, as someone that owns property with an "unsightly" (whatever that means) structure on it, I'd just throw your request in the trash.

Is there another avenue for me to get the answers requested by my client?

They had a loan request for $3 million.

Also, the case workers were taking forever to process RFTAs, only to request lower rent in order to approve - why deal with this when there is strong demand from qualified non-voucher applicants?

(They requested 24hr to review any offers).

Post a letter on each door letting them know of the new ownership and providing information on how to report maintenance requests, make rental payments, more - if any of that has changed as well. 

There are services which allow them to complete the application themselves online; some services even allow tenants to sign a lease with you online using the same platform (and offer other tools like online rent collection and managing maintenance requests). 

I get to pick who I want to work with, I set my own hours, I never have to request off for vacation, and I work from home.