Cozy.co looks to be quite attractive and I've gone through their initial account setup, linked my bank account and all seems smooth so far - but I'm curious as to how the service functions in practice and if there are any "hidden" fees that the tenant or the landlord would potentially run into and be cause of shock/disappointment. 

I would suggest you start with vacant land as the prices for occupied are going way too high to make them attractive for a flip and your redemption period is shorter on vacant land than occupied may be if it is a homestead.  

The high end nature of the St Louis market properties attracts higher quality tenants and provides a better exit strategy environment than most other markets' properties."

Only to attract more buyers.. is the house substantially in a bad shape?

The first order of business is attracting good tenants to begin with.

That said, of course, it need not be YOUR cash or credit.You'll want focus on partnering and fund raising at this point in your investing career.Especially, learn how to attract and engage private lenders.

Prices are lower which is good for buy and hold and people will be needing creative ways to off load their houses which makes Subject To attractive. 

It's mainly geared towards attracting new investors and also signing them up for the company's coaching business, but the knowledge and content is still top tier. 

However, I often see very attractive deals but they are 3,1 or 2,1.

They rehabbed and improved the buildings and made them attractive to renters. 2 years ago the Berlin State voters approved forcefully taking the private property and making it public housing again, managed by the same types of bureaucrats, that ran it into the ground to start with!