I have seen people do flips and continue to do that to escape the "rat race" but others acquire properties doing once a year by putting 5% down and over time it will easily get them living comfortably.If I had it I would find a property in a solid area for airbnb (where the numbers make sense) and make my place an airbnb while living there or get a roommate for the first year with me then airbnb it out.Getting a real estate license helps as well so you can get $$$ for referring people or put $$$ towards the down payment or closing cost from what you would make as the realtor on the deal.

We lease by the bed and are concerned that students will lock their roommates out, causing additional safety concerns and lots of headaches. 

We have a roommate lined up who would pay $1,100 towards it.

If the mortgage on the condo costs you $2750 and you can get half that from a roommate, you guys have the ability to stay somewhere you actually desire, and you're only footing half the bill but getting all the benefits.

As you can imagine this is scaring the other roommates.

Is it possible to actually have your roommate paying most of your mortgage in an expensive city like NYC, via house hacking?

In cases where I rent a room I just rely on checking they have a professional health care license and a job in the area but that is only because the roommate is my son.  

You run into the issue of one leaving and them bringing in a new roommate. 

I would be living in the house with 2 other roommates to hopefully offset the mortgage and other expenses.

If you can stand roommates, then buy a house with the most number of rooms you can afford and rent by the room.