why not just buy something, rent it out and keep doing your job? it's not like you need to be on it full time to rent out a place. even if you have to do quite a bit of diy.
i rent out rooms in my place and it's just a perfect side gig.
my renters have proven to be very reliable so far. you have to realize: most people are reliable. people are not looking to stay for two months for free and then get thrown out of the door. most people are not bad people. so whatever you do , it will likely work.
i use fb groups and my personal connections 50-50. i would not use Airbnb because it is usually for the short term. it is important to talk to people before you let them rent. try to judge their character. in general i avoid people who seem too cold/business-like about it, because i know people who like me stay longer and will be more fun to live with.