We did not buy it ... we received it from our parents - they were considered co-owners of the property. Upon our Dad's death, our mother became sole-owner. In order "give" us the property without cost, my brother and I were listed as co-owners with our mother by means of a "quit-claim" deed. In this way, there was not a "transfer of ownership" from the current owner since our mother was still co-owner. At her death, her name was dropped as co-owner.
There was no sale and we are still considered to be "original owners" - thus the reason we are "grandfathered" with the land use