I'm working on a few BTR projects where we’re building single-family and townhome-style rentals as a product that competes with Class A apartments—but with more space, garages, and no shared walls.Would love to hear how others are thinking about capital stack, returns, and partnership structures in this niche.

We actually consulted for a company in Chicago that developed an "automated" application screening product, which is now on the market.Very confused about your post as you are asking a baseless question - due to the fact you are providing zero information about how your tool will work."

As in the company is going out of business or the company is doing poorly can they demand full payment??

There is a place and time that it makes sense, but as long as you get any cashflow that first year, father's time will likely help you out after that as long as you have a quality product. 

To avoid going through the same poor experience, keep reading.Even if someone gives you a referral here, do NOT make the mistake of assuming that the PMC will meet your expectations, just because they met the expectations of the referral source.In our experience, the #1 mistake owners make when selecting a Property Management Company (PMC) is ASSUMING instead of CONFIRMING.It's often a case of not doing enough research, as they don't know what they don't know!

I've seen many poor investments made with single digit cap rates and even negative cash flows in hopes of getting great appreciation. 

In the absence of sufficiently comps, expect a very poor valuation.   

What type of loan products would be available for an LLC buying a house?

I first got interested in real estate back in high school after reading Rich Dad, Poor Dad and dreaming about financial freedom.

In fact, it is a poor strategy.