We bought a house in NC. About 3 years ago. It was one parcel split in two. The owners Daughter still lives on one parcel. We'll I am 95% sure my septic tank is on the other side of the fence onn their parcel. But the seller ,which didn't own it long and was the Mortgage Broker for the house Claims it is in the front yard.What can I do to hold up her sale until we clear up where the tank is.