This way, you would have two income sources offsetting most, or all, of your mortgage payment.

I been looking to buy my first rental property I already got Pre-approval loan, down payment and criteria for the house.

FHA also allows some flexibility with grants and assistance programs, which could help with closing costs or down payment.

You make all of the BAH payments back tax free for you.2.  

My plan is to use my HELOC from my current primary residence as the down payment.

You will need down payment money, You will need cash reserves Money, you'll need closing costs money, and you will need to get a bank loan.

I know very little about legal precedent but I'd expect the major meter manufactures (selling into the utility space) to be well incentived to challenge these items best they can, and they have money.Here are the issues, and the reasons that the difference between an air forced system and a boiler/hydronic system are not meaningful for this discussion (ie efficacy issues of sub metering exist for either when method of measurement is measuring heat at point of delivery):In either case, the blower (or pump for a boiler) is the method of 'moving' either air (central air) or water/glycol or equivalent (boiler etc). 

I’m looking for a structure that would at least allow me to break even, or create capital through something like the BRRRR method to use for future deals.

Furnitured finder is great for finding professional traveler and I like apartments.com because of their payment setup if free for the tenants and myself.

If rates do go down significantly, it will be more of a sign of economic instability.I recommend continuing to save monies until you come up with enough for a decent down payment.