No, the mortgage company is not in privity of contract with you so the mortgage company is no way liable to you for lot rent. The mobile home's owner is liable to you for the lot rent. You can see if the home is foreclosed on and if so, then the mortgage company may have to move it but again it all depends on if this is considered abandoned property and if you can take without any legal requirements. Check with your state treasurer on abandonment laws and check with the mortgage company if the home is abandoned. You can sue the mobile home owner for the back rent owed but if that person has claimed bankruptcy, you may be in a tough battle.