@Vincent Paventa You may want to skip trace owners of rooming houses in your targeted area and call them directly, this would probably be your best source of sound advice.

The rental above cash flows about $5,000 a month and helps offset the mortgage cost at $6300/mo.My question is: we have a lot of equity built into the rental, but the mortgage rate is so low that my calculations show shifting the debt from the primary residence loans to the rental as being a wash with the tax savings. 

I know exactly how this company and franchise operates.

What data do you gather and what tools do you use to optimize this process?

If you have specific questions about property management, I'll be happy to help!

What resources / vendors exist out there for this?

I know that co-star offers this, but I don't have that budget, I am okay with spending 100-200 a month for software to practice with and learn.

However, this doesn’t seem right to me because there is no taxable gain or depreciation recapture.

If this was your first year getting a 1099, then there might be a small chance that you could get away with just this year's 1099.....HOWEVER, since you have been 1099'd for 2 years now, then the mortgage lender may request tax returns before extending a mortgage. 

Did you achieve this with apartments in Vegas?