There are too many benefits to reap such as principal paydown, tax savings, and appreciation on an OO home.

BUT, if me and my girlfriend lived in the 2bd/1bth unit and rented the two 3bd/2bth units, we could potentially have the principal & interest covered and live there for free and only cover CapEx/Repairs.

.) - Usually 6-12 months of P+IDSCR = NOI (Net Operating Income) / PITIA (Principal+Interest+Taxes+Insurance+HOA)The property value is determined by a "rental" appraisal. 

It is going to be interest only payments until I can refinance to pay off the principal balance.

@Arman A. my vote is:Option 2 - Sell the place and buy two properties possibly a duplex.I say this because if this is your principal residence you can avoid capital gains taxes.However, if you are looking to buy two properties in California, that might be a difficult task. 

Assembled the team (principally architect and builder).Brought vision of creating a unique, beautiful ocean front home that did not copycat other home designs in the Outer Banks.

Considering principal and interest, it would be $1802 for $450k purchase (3.5% down) vs $1888. 

Someone might sell a condo to me 2b2b —$220krent: $2150750 cash flow plus 300 principal pay down each month.  

You calculate: Rent - payment of principal - interest - taxes - insurance - maintenance -capital expenditures -vacancy = cash flow.

At the end of the month as bills begin coming due, I pull that money from the HELOC and pay the bill, restarting the cycle.This works so well because the 1st replaces the mortgage on the property it applies to, "freeing" that cashflow to go directly to principal.