Do people rent rooms out of financial necessity?

So I'm in the process of buying a home and am already thinking of whether I would be open to the idea of renting out a room to help pay for my mortgage.

I've been searching the "Rooms Wanted" ad's on Craigslist because I'm very picky and would almost kind of feel more comfortable making the selection of the person myself rather than having a garage of people call me up.

I'm in my 20's so I don't know if I would want someone drastically older than me, but a little older wouldn't be a big deal. Some of these people claim to have good jobs, and it makes me wonder-- if they have such good jobs and stable employment than why on earth would they want to rent a room?

For me personally, renting a room would be a last resort, if I had to do it out of financial necessity to have roof over my head, than so be it. But, I would fight with everything in my power to have a place of my own, even if it meant working longer hours or having a second job.

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