The difficulty of changing or replacing a lock varies, but if no new holes are needed, replacing a handset is a fairly straightforward, DIY job.
Are you rekeying your home? You may want to hire a locksmith. Locksmiths can make key copies for all the locks in your new home. They also can provide new keys for you and members of your family. Rekeying all the locks to one key makes life easier. This ensures that you do not endure any additional difficulties or limitations in accessing your new or existing home.