I personally develop quite a bit in a neighborhood where the zonign laws are already quite prohibitive and to make matters worse, the community as a whole fights all housing from being built in the spirit of stopping gentrification.  

My thoughts: East Bay:- Close to a BART station to traveling medical worker/corporate person could hop on a bus/BART to work: El Cerrito, San Leandro, Hayward, Fremont, Walnut Creek, Pleasant Hill, Concord, Dublin, Pleasanton- Maybe Richmond, Antioch and Pittsburg but some parts have a lot of crime. - Going further out Brentwood and Oakley have appreciated quite a bit and have pretty good schools- Something with potential to add value: ADU attached to the main house or separately in the backyard in the future to get additional rent.

I use a broker, they do the leg work and since their interest is in my success, as opposed to an insurance sales person who's only interest is making commissions.

This type of loan is based on the property's income, not your personal finances, which makes it perfect for investors like us.

The exact definition varies from person to person, but I mainly consider them <$40k reno and hitting those items.

However, it is mostly geared toward a person who has a W-2 job themselves, which is not the case for me, so there are some applications that I am finding confusing. 

(And best case it was a rental for 17 years then a primary for 3, making only 15% possibly eligible.)Personally, if you and he are both 100% sure of the facts I would first reach out to a qualified intermediary (a person who handles 1031’s).

Your personal assets are protected with a viel, which can be pierced under certain circumstances.

The rationale being you are reducing your personal housing costs as the rented unit will be covering some of the costs. 

Personally, I'd do it.