I have a mortgage with Wells Fargo. The house is on the market now. I have a customer who wants to assume my mortgage. Could that be possible?
Yes, it's possible.
You'd let him move into the house and make the payments on your mortgage each month.
This is risky, as you might imagine - he may quit making the payments.
The other way is that he simply gets a loan for the purchase of the house, and that loan pays off your loan.