I would go with what produces the most cash flow at the end of the day.

Multifamily real estate investments, such as duplexes, triplexes, or fourplexes, have the potential to increase total cash flow as they may produce several sources of rental revenue from a single asset.

Introducing a fair negotiation on terms with (1) end price, (2) length of term and (3) cash up front could likely produce the results you BOTH are looking for. 

You can sell a few to pay off the rest or 1031 them into passive income.Any property you buy today should appreciate about 4.9% p.a. that's been US average (insert a % you believe is right, I believe Milwaukee may actually beat this number) over the next decades and your downpayment is leveraged 4:1, so that in itself produces a lot more equity over decades than you could ever safe up. 

I challenge you to find a single reputable source that shows San Diego residential RE has not produced outstanding ROI.  

@Dan Barth I would have a professional do the mold test that is certified to do so, these home tests are bogus and almost always produce some sort of mold.

most top producing resi agents avoid investors like the plague. 

You are betting your money on the neighborhood and the property (and the client base that will attract), hoping to produce a return greater than what the S&P 500 would produce over time.

We do not need it to produce massive cashflow like many investors are after, because our LTR's produce enough cashflow to help float the portfolio.    

A smooth sea never produced a skilled sailor (Franklin D.