I searched for properties that stay on the market for a long time.

It was a good learning experience, but it made me realize that staying away from major rehabs (for now) might be the best move until I have a more reliable system in place.That said, having family in the area like your sister and brother-in-law is a huge advantage!

We had hoped to rent our house for short-term or mid-term stays.

The substitute of collateral was more of a scenario where you sold for $155K, and instead of paying off the $88K loan in your scenario, those funds stayed at the title company and were used on a cash purchase happening nearby in date. 

Start small, be patient, and stay connected with local meetups and online investor communities for support. 

Stay patient, something will come up that makes sense.

So I stay tuned to see the ending.

My 2 cents: it sounds like you've got to pick a lane and stay in it, become an expert, and level up in that lane.

Are you looking to stay in the city? 

I personally would stay away from condo-tels as they will be even worse and you'll have less opportunity to cash flow.