My concern is the markets they're choosing to purchase into at the moment.

I'd recommend taking your time when choosing a market and look at all of the economic drivers that are helping the communities expand.

I personally choose to utilize the traditional LLC for my first few properties and it has treated me well.

Also you can check Meetup for local investor groups as well as there are some smaller ones around also.I'd say one of the biggest steps is choose a type of Investing.

Most importantly, choose a market that aligns with your goals!

Hello - I am wondering which MLS to choose for New York City and how to get an MLS ID? 

Make sure your lease stipulates its a "shared property" and list all the rules to make sure they toe the line, garbage, one vehicle(where parked), noise, no personal items in yard, everything you can think of or choose/whatever.

Have to agree with @Jonathan Styer about being VERY intentional if you choose to do this.

I would recommend that you screen your tenants and have them complete a background check with a company of your choosing and not just accepting Zillows in house background check that some of the tenants already have.

if I'm choosing one market/property vs another.