The GNMA and FNMA also actively discourage the practice and have issued written guidance stating that lenders should not be requesting comfort letters from accounting firms.Unfortunately some lenders continue to do it as they want the assurance of an audit but do not want to pay for it. 

Having said that, I can assure you that maintaining contractor relationships, scheduling the work, overseeing the work - is killer time consuming and is definitely a loss leader for your PM.  

Her mom assured me she would be out by then. 

That lowball offer was from, I'm guessing, a wholesaler, and the agent wanted to assure me that it was a "scam."

My friend assures me that while young, (early 20s), has a girlfriend and was told that he is a hard worker and should not be a problem. 

Yes, that's enough of a deposit to borrow another say $150k (unless you're really gung ho and want a ~95% primary mortgage), but then that brings into focus your DTI as it relates to how much income you'll derive out of your newly refinanced ~$335k investment loan - together with your yet-to-be-approved hefty new primary mortgage debt.For your sake, I hope you already have very good assured income. 

I would only sell if I did my homework (which sounds like you are doing) and could be %100 assured the tenants would have to move out after house sells.

How can we assure ourselves everything won’t fall at closing and also we have asked our realtor for a renters contract a few times and we haven’t received one which is something we should be familiar with , so a template for a renters contract by our colleagues on here would be very helpful.Thank you all in advance 

You need to find a mentor or a confidant to give you some assurance.  

They are in Chula Vista & Bonita, I have consulted with a Vacation Rental company and they have assured me that these areas, will not be subject to the new SD STR Restrictive Ordinance that recently passed.