These requirements shall apply to all VRBOs, regardless ofwhether they qualify as a principal land use or an accessory land use of thelot.C.

For me, I was able to justify the purchase knowing that my principal pay-down alone once I have tenants in the property would be $1,500+/month.

Which means your cash out is the difference of that minus your current principal. 

If you're putting $22,000 into the deal, think about your target return on that money.Calculating returns on rentals gets a bit abstract when you consider appreciation, principal pay down, and tax benefits.

Without knowing your particular circumstance, I think that when you factor in the total addition a San Antonio or Austin property could have on your net worth (when factoring in rental income, long term appreciation, principal pay-down, and tax advantages), it will still be a strong long-term investment.

Particularly if you plan to stay in the military and generate income in that regard, allow the cash-flow, principal pay-down, appreciation, and tax advantages of owning this 4-plex continue to work to your advantage. 

The people signing on the note are called Key Principals. 

If you wait long enough and you have a lot of principal paid down on the property (i.e. you own less on your mortgage) you could cash-out refi even if the rates are the same and the value did not go up.

Chapter 27; $500.2 does not allow for more than one principal building.4.

Just to put numbers to it:Per 100k a 40 year fixed loan at 6.99- $620- first month: 38 to principal and 582 to interestPer 100k a 30 year fixed loan at 6.99- $665- first month: 82 to principal and 582 to interestPer 100k a 30 year fixed loan at 6.25- $616- first month: 95 to principal and 520 to interestAs you take a 30 year loan out to 40 years you experience diminishing returns.