I actually found my roommate on Craigslist, 5 years ago. I met with multiple people before I offered her the room. We have our ups and downs, but ultimately its been a good experience.
Honestly, I'm not sure you are going to keep your sanity if you are territorial and easily irritated. It starts as a landlord-renter relationship, but if it doesn't evolve into a more well rounded relationship, I see trouble. You don't have to be best friends, but there will be plenty of give and take. My roommate always piles dishes in the sink, which drives me crazy. Its just not something she is going to change (she does eventually put them in the dishwasher). On the flip side, I do plenty of things that make her want to murder me. If its going to be "your way or the highway" save yourself some stress and find a different way to make a little money.
Imagine dealing with all the bad habits of your spouse, or sibling, or friend, but without any love for that person to counteract the annoyance. Can you handle that?