I don't have experience with the igloo home lockbox, but sounds like a good option, where you can create unique codes, or require people to use the bluetooth of their phone to open it.  

Cheaper way,  install higher end rugs that will match decor  and color schemes.It will help, not only on the floor noise but overall noise .As a contractor, if you do the sound board in ceiling below then just install it over the sheet rock and install a new layer of sheet rock. 

I was in a unique situation where all my income for my rentals was from Airbnb. 

This must be a unique situation because when I talked to the lady at the Sheriff's office a few weeks ago she told me that all liens are generall wiped clean at the Sheriiff's sale. 

In all, your situation is pretty unique and I think house hacking would be an awesome start to your investing career.

For me I use unique ones as that is easier. 

Welcome.This is not comprehensive, because every area has unique things to consider when analyzing a STR deal.1.

The property is a unique townhome/mid century modern/half a duplex and the comps used were condos. 

The property is a unique townhome/mid century modern/half a duplex and the comps used were condos. 

The major colleges, each is very unique and it's best to work with someone who is highly experienced and connected into that specific university area.