The underwriting process is certainly more arduous than most acquisitions but through my personal experiences some of the lenders are far more knowledgeable about the requirements and make for a far easier process for both seller and buyer.

And I can recall only once that a title company released earnest money to the Buyer without requiring the mutual release - worked out in my Buyer client's favor so I didn't complain.

Assuming 7.5% interest rate, the negative leverage would require you to put way more than 20% down just to break even.  

You either have verified income and meet the other requirements, or don't. 

Tax law requires it.

My buddy sold for ~$500k over its existing use value and no contingencies and did not even convey existing tenant’s deposit.  

With that they may be able to recoup from their renters insurance (hopefully you require this)  If locks are damaged and the unit isn't secure you would need to take care of that right away.

Dwelling/Fire policies require that you request a limit for contents.3.

The US taxes global income which dramatically increases the reporting requirements.

If you ask the manager to justify a fee and he starts hemming and hawing, move on or require them to remove the fee.