We play musical locksets from one sfr to another. One thing we always do is make sure every lock on the house is keyed alike. We install new locks immediately after closing on the property. It's typically a mish mash of locks on the doors, some of which we don't have keys for. We don't have many "turnovers" but did change out the locks each time and would never consider not changing locks between tenants. We just buy inexpensive locksets at Home Depot and change out the whole knobs rather than trying a rekey type system.