The lender would have had an appraiser issue a opinion of market rate rent for the apartment on your duplex so that's a start on what the rent should be.

Pricing - most bookkeepers I know are transitioning to flat rate pricing that includes software costs, based on the complication/volume of your business(es).

Depending on your situation, PMI may be higher and you may have a slightly higher rate. 

It probably helps that I currently have my mortgages through this bank as well because it has had the most competitive interest rates each time I have gone for a loan.

I contacted a title company to officially record the sale, but they are requiring 3 separate closings (and tons of extra fees) because there will be 3 liens/private mortgages recorded (one is the original mortgage that I want to reassign since the interest rate was very low; the second will be held by my son to my daughter for his portion of the equity in the home; and the third is the difference which will be between my daughter and my other LLC). 

In SFR if prices rise supply drops, high interest rates makes cash flow for new investors go away and supply drops.

@Scott AlvarezThere are 3 main parts to a seller financing deal: down payment, interest rate, and price (4th would be the term).

Well you cant BRRRR at 7% interest rate in a market that pays 3% Cap Rate on rentals.  

Also check the fire departments ISO rating.

I was wiped out as second lien holder which got me to thinking about legitimetly becoming a private lender.My question is if I already make 7.5% off a few of my 250k condos, then how does private lenders (not hard money lenders) make money off charging 7-8% returns when they can just purchase condos in cash for the same CAP rate?