FHA is typically for borrowers who need a little more wiggle room with DTI (Debt to income Ratios) and Fico scores. 

@James ShenThere're dozens of threads discussing this, just search for them, like these:https://www.biggerpockets.com/forums/51/topics/795929-questions-to-ask-a-potential-accountanthttps://www.biggerpockets.com/forums/51/topics/792277-how-to-test-your-cpas-technical-competencehttps://www.biggerpockets.com/forums/51/topics/528033-must-ask-questions-when-interviewing-a-cpaTax attorneys are only necessary if you're planning to take the IRS to court, otherwise they're just a more expensive version of a CPA or an EA (Enrolled Agent)

We often see zero vacancy as have a new tenant for day old tenant leaves it's 650+ credit scores.

Sounds like a total score!

Short version of my question... 

My credit score is around 780.

I have screened tenants that have a 650+ credit score but am deciding whether or not just first months rent, and security deposit is acceptable.

I am currently just using the free version of AirDND and confused about their pricing.

If it is for a credit score/background check you can purchase them through companies that sends the invoice directly to the tenant.

I told her that I couldn't due to her not so great credit score because of a recent bankruptcy.