I retired from 25 years of nursing and began to do this full time with my wife Sue.

Will you be looking for long term families (focus on crime and schools), student rentals (close to universities), travel nurses (close to hospitals), vacationers (close to travel destinations), etc.

A few years ago I went to an auction preview of a former nursing home about an hour away. 

Therefore most travel nurses have a hard time getting a traditional home loan.

As far as your tenant being safe in the health care industry, as strange as it sounds, many doctors and nurses in the US are getting laid off right now.

Nurses, Firemen, Construction..... use AirBNB. 

The nurses are usually in a 90 day contracts.

Trying using the keyword "traveling nurse" on your listings if you're near to a hospital.

And of course their independence to not rely on family or be "locked in" at traditional assisted living or nursing home environment.But, the really large returns do require full hands on management, at which point you can likely make a boat load of money, but you are working for it like any other business.On the truly passive side, I just wonder how many people are in the market to rent a house in order to bring in their own tenants.

Another market to plug into are traveling healthcare workers (nurses, physical therapists, physicians assistants, etc) www.furnishedfinder.com - they rent shorter term than a long term tenants but longer than VRBO & Airbnb.