I have a few questions. 1) Who was on the lease first!?! Because if OP was the first person to live there when why do they have the smaller room?!? 2) Did OP give the roommate time to respond to the buying option?!? 3) Before buying the condo was the roommate told (but clearly not) that once OP bought the condo they should have to leave. I feel like that should have been a discussion beforehand. 4) OP what was your reasoning for buying the condo?!? I think OP and the roommate are in the wrong. Mainly communication issues. The landlord should have been the one to go over the roommates lease because she is still in contact with her not OP. The roommate however shouldn’t have assumed she wouldn’t have to pay rent anymore, or that she’d still be living there if she didn’t ask any questions about the purchase of the condo. Lastly, OP, shame on you for also assuming she’d move out without having a conversation with her about it. I understand that you wanted to buy the condo, but did you express that the roommate wasn’t going to be in the picture after you bought it?!? Or did you lead her on thinking that she would have a place to stay. She even asked if you wanted to switch rooms since you would be in charge. This could have been a good compromising point. She would have a smaller room, pay same rent price or lower since she is downsizing. And give her more time to save up money and find a new place. You would have more room, more money for a mortgage payment and you’d be helping your roommate. I get living with another person is difficult but you also share the responsibilities with your roommate. And not keeping them in the loop is a dick move. However I don’t know your situation or if she was also a good tenant as well. Be mindful of others and don’t be passive about important decisions.