In answer to your question, an N number can be changed for a fee by an owner or new purchaser if the requested Number is available; as the N number does NOT have to remain on an assigned aircraft for the aircraft's life. The change is possible with a re-registration fee and new number availability.
An N number, if available, can also be put on hold for a fee, also. (There are certain FAA restrictions/limitations on N numbers).
This site has removed, in the case of EAB-aircraft (Experimental-Amateur Built), the registered names of the original aircraft builders/registrars. That can make for some confusion, unless the FAA Registry is consulted to trace specific N number aircraft ownership, which retains (aims to) through various subsequent purchasers, the original registrar's name. Aircraft escrow companies can also trace previous registrations of a particular aircraft, sometimes as a courtesy, sometimes for a fee-it depends....There are also shysters about who falsify aircraft in registration-not always caught by the FAA.
Subsequent purchasers of any aircraft can apply for an N number change if the number is available, subject to the FAA guidelines for N numbers. Some aircraft, production or EAB have been re-registered multiple times through subsequent sales with possibly different N numbers, with required fees paid.