Real Estate-Kings Mtn, NC?

I am the primary signer/owner of a mobile home (3/2) which is located in Kings Mountain, North Carolina and my ex-wife father is the co-signer. All payments to the mortage company are being paid by her father and mother. I have been living in Tampa, Florida for 7 years and I am in the porcess of purchasing a home in the next 2 years. I contacted my ex and her family and told them to fill out an application so they can take the current mortage out of my name (so they can be the primary) but they said they cannot afford the down payment the mortage company is asking for. They mentioned that the mortage company said I could sell them the house. I am lost. I do not know what to do. I am looking for some information on what I should do. Thank You for your time.