Combining them put it into a 30 year mortgage- which was not possible for either piece singularly. 

Contribute to HSA the maximum you can, then invest to get the best possible returns and wait.

It seemed like a long-term play with less price or industry volatility.

Its possible in your area that garages and parking are more valuable than units - this is your appreciation. 

Cross-Collateralization – A lender may finance the full $160,000 purchase by using your existing properties as additional security, lowering their risk and possibly reducing your down payment. 5.

Yes possibly!

Lets say your accountant tries to write off as much as is legally possible when it comes to lowing your taxible income so that your tax burden is less and you pay less taxes.

As I take in as much content as possible from listening to the Rookie Real Estate podcast, I feel drawn to building multi-families and renting them out.

When you specifically mentioned STR experience and the possibility of something with some added "personal value" bells started going off. 

Are they doing everything possible to expose properties to the broadest possible market?