Determine the remaining equity in the home by deducting the mortgage balance from the value. Divide the equity in half to determine each of your proportional shares in the value of the house, provided you are a co-owner on a 50/50 basis. You may also need to adjust equity for unequal contributions made by one of you to the home or maintenance. A mortgage buyback is when the owner of a property pays the other owner`s share of the property`s equity, so the co-owner can be exempted from the mortgage and removed from the deed as the owner. Hire an expert to generate value for your home. Sometimes you and your co-owner can choose that each mandates your own expert and the average value.