I have experience in single family fix and flip, 1-4 family rentals, small apartments (10-30 unit), 100+ unit apartments, development, commercial retail, industrial and office.

Their pay-as-you-go model allows flexibility, so you only pay for what you need.

I would personally put them in notice just because they never tried to communicate it on the back end of fixing it.

Damage to the garage, depending on how much and what it is, charge them and get it fixed. 

If things to sideways, the money raiser usually has no leverage or even any authority to fix the problem.

That is for you to model and assess.

The main reason I ask is because that is significantly below primary residence mortgage rates let alone any investment loans, if you can get rates like that I might need to make some changes on my end hahahTo answer your original question, assuming all else is equal long-term fixed rate debt is valuable. 

Expect 30-year fixed terms for the most part.

I may be able to STR a spare bedroom but that would be for later.Background: A fixer upper, but I do not know how much fixing is required. 

Foundations actually can be fixed.