I actually had this happen to me last year. The FC leader had a falling out with everyone in the FC. They all left over the weekend and when I got back on on Monday, It was just the FC leader and me still left in the FC. I tried contacting her for a few days because she had locked the house and I couldn't get to my room. I wanted to transfer servers to play with some friends on Malboro, but couldn't demolish my room.

So ultimately, I contacted a GM, gave them the run down of the situation, and we found that the only solution was for the GM to forcibly demolish the room with all of the furnishings inside. Luckily, I never spent any real money on the items that furnished the room, but there was quite a bit of gil invested in those furnishings.

I have sworn off all housing ever since. too much drama surrounds it and I play games to have fun.