The best way to resolve the situation is to have a face to face meeting with your sister as to the need for her to transfer registered title to the mobile home to you as she had promised in light of the fact that you have a FEMA loan with respect to it since you represented to this federal agency that you in fact owned it.If your sister refuses to tranfer title to you regarding the mobile home you need to consult with an attorney that practices in this area of the law in that it makes no sense for you to be paying on a loan for something that you do not own.