With 9 properties, 4 paid and 5 financed, you could clear a bunch of cash flow, pay for rent in SFo area or almost and if you buy something in SFO, you could do the home buyer jumbo loan thing and pay the mortgage with the passive income your tenants give you each month.Keep in mind that a 12plex is a commercial real estate property that does not apply for traditional residential financing and the only way to increase value is by improving the rent roll.

We made several improvements to the property when we got it - a totally new gas line, a totally new water line including all the lines from the street and pex plumbing installed.

These updates modernized the property, improved its curb appeal, and significantly increased its market value.

I'm no tax advisor by any stretch, but I believe there's significant financial criteria to meet such as like 50% of the purchase value needs to be added as improvements to the property. 

It was a bit confusing when you said that a buyer can only get a credit up to the closing costs, but then later used an example where the credit was more than closing costs and the buyer could use those funds for improvements.

Because a lot of landlords are pushovers and will do the improvements.

Once you make assumptions about redeploying your periodic note payments, such as the rate of return earned on the reinvested amounts and the periodicity, you'll see improvement in the CAGR for the note.

I think starting with a mutil family, adding value to it (making improvements if needed and raising rents), is a great way to get started.

Mortgage rates will eventually come down and also improve cash flow for any potential refinance for capital accessed now.

I recommend you talk to a lender and get real clear on what you can qualify for, what you can do to improve your borrowing position, and make sure you have your finances under control.