Well FL, some things never change. I have to tell you that this might be an opportunity for you. I just had my house appraised because I refinanced. I was pelasantly surprised - and I'm an appraiser! - just not a residential one. An appraisal is an opinion. For about $300 you can get your own appraisal done and I would suggest that you do so.
Please suggest to your L that you have an appraisal done on your behalf, or jkust sell the thing. Sometimes these people screw themselves. My X (before he was the X) had his friend come into the house to appraise it without my knowledge. He appraised it high because he thought I was buying out my X. But my L got hold of that and the X then wanted to remain in the house, so he had to buy me out. Maybe she should sell - then you would know the true value of it - that is the only way to tell. That way there would be no buyout and the proceeds would go to the two parties. After all, she brought this up.
