You are offering them a convenience btw and asking to be rewarded for making their life easier isn't unethical as long as you are up front about it.

I have used the BiggerPockets BRRRR analysis tool, but not sure if I have used the correct assumptions.Property:  1241 W CHew, Allentown City PA, 18102 (2-unit house)- listed for $73k- Offer: $40k- Closing cost: $9k- Repairs: $16k- ARV: $90k- Rent: $1,800 a month- Vacancy, Maintenance, CapEx: 10% each- Water and Sewer: $100 a month- Insurance: $100 a month- Property management: $180 a month- Property tax: $261 a monthThis leaves me $232 cash flow per month if I refinance it at $90k at 5% interest rate.

The other requirement (that they will absolutely not waive) is to have 6 months worth of PITI (principal, interest, taxes, insurance) reserves available.  

Plug in property taxes and insurance.  

Everything I've been reading leans towards an LLC because there's more flexibility, etc. if I even need liability protection outside of good liability insurance. 

We were supposed to close Sept 7th but the buyers’ insurance and Title Company put the brakes on the sale until after Irma passes.

The $990 is including all insurance and taxes correct?

I learned (newbie mistake) that the unit is actually in a flood zone a and the lender requires flood insurance.

Just to give perspective, they have worked very hard their whole life, is still working just as hard, and never really had anything to show for it, lived very modestly and never acquired any kind of wealth nor a real retirement account.

I use Ally financial for my rental checking and rental reserve account, about the best interest rates you'll find for FDIC insured bank accounts.