Focus on what the rents will look like post-renovation with 4 units instead of 2, and have a clear game plan for refinancing to pull your capital back out. 

Short term rentals in St Pete are technically illegal but it doesn’t stop hundreds of other investors from doing it.

Welcome to BP and come on over to the Short Term Rental part of the forums.  

Short-term rentals are becoming oversaturated in certain markets plus anti-STR legislation is resulting in some of those properties also converting to long-term rentals.You already have the operations experience by self-managing.

Commercial is a totally different ball game than residential, so connecting with a commercial broker will definitely make your life easier.

I'm trying to analyze my first property and not sure how to set it up to run the number using the calculator tools here. 2 of the units are successful Airbnb short term rentals, and the other two units are month to month rentals to existing tenants.

It falls short of the 1% rule which with current rates is not sufficient in most markets to have achieved real cash flow after properly allocating for sustained expenses. 

. - some strategies I've seen California investors use to lessen negative cash flow: house hacking, mid-term rentals (people temporarily displaced from home renovation or insurance reasons like fire), rent by the room, Short Term Rentals. - The ultimate house hack, live in the small ADU unit and rent out the two levels of the main house on AirBnb in San Francisco (I would have thought STRs are oversaturated in S.F. but it worked for them and they stay fully booked).

Not to mention short sighted as you are now finding out.

Negotiating felt like a game of chess—except I was playing against a grandmaster, and my queen was missing.