And what I have seen and experienced, 1st and 2nd hand, is when solar is PROPERLY utilized as a feature, it's lends a ROI of about 150% on just the unit pricing/value increase, which is saying 0 calculus of impact on utility offset's. 

I know long-term rentals are not as lucrative but I want to make sure the numbers work at that conservative calculus and build from there.  

If you are into these for the long term probably better to bite the bullet and refi into something fixed, you can always refi again if rates come down, but that calculus depends on the specifics of your AMRs. 

Here, the delta that the capital is generating for me (and opportunity cost of not financing the vehicle) would be 6% of $20K.So again, my calculus is that if the capital can generate a higher yield than the interest I would be saving by paying off my debts or not assuming them in the first place, then I say yes to the debt.Of course, it is always important to factor in the risk of the expected yield. 

If the cost of living factors in heavily to your calculus, consider the non-touristy areas of the DR.

When spouse and kids enter into the equation, the calculus changes.

I also don't invest here either which changes the calculus.

Don't worry; we're not talking about complicated algebra or calculus here.Instead, we're talking about some straightforward calculations that help you make smart decisions.Crunching the NumbersDoing the math in real estate involves crunching numbers to figure out if a property is a good investment.

On paper it looks like Cartersville is a little bit better but I'm wondering if the shorter commute from Douglasville to Atlanta and the eventual development of the west side of the city will ultimately change the calculus 5-10 years from now.

No body does calculus on their first day of math.