I have been looking at sf homes with comparable SqFt to one of the units, as well as the units combined to try and get a feel for what this is worth.

air filters is a must. a friend of mine had one of his AC units go down because the tenant didn't change the filter.

Your first move at 18-21 should be house hacking (buying a small multi-family and renting out units).

I'm looking to exchange a multi-use property I own in the Bay Area for a multifamily property in Phoenix (looking at 15-19 units).

@Craig Daniels I’m getting at least $200/unit/month and never put down more than 20%.

Many opt for other investing methods in their SDIRA like private lending, crypto, private equity...anything except collectibles and life insurance.Note that a Solo 401k is exempt from UBIT on leveraged real estate so if you have self employment activity and no full time employees save for you and your spouse you should consider the Solo K as an option. 

Expensive unit at the property goes out, takes money to fix.

The current monthly payments from all units will remain constant for 35 years, but obviously the value of those payments will be worth far less 35 years from now due to inflation.

I do see lots of self storage and warehouses going up, so my default assumption would be that the old shopping malls do NOT trade for less than build cost, but it's possible that the marketplace is not perfectly efficient. 

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