Keep an eye out for a granny flat set up. We have a 3 bedroom home with a granny flat attached.
Ours is rented, but we have a granny flat, fully self contained right down from the washing machine/furniture/ fridge etc to the knives and forks that we rent at $160.00 per week.
Best thing about that sort of set-up, is you lock it and forget on weekends.
Also, with ours, we've set it up with seperate water and power and car accom, if fact, even seperate driveways.
They don't come up often, but they do come up.
Renting a room...... bit of a worry, unless of course, it was a swagger you were renting a room off.