Replacing the locks on interior doors is a quick and easy task that a professional tradesman will be able to complete in next to no time. They will simply remove the old mechanism, taking the door from its hinges if necessary, before replacing it with a similar lock. If you are changing the style of lock, or you have a non-standard model, then your carpenter or joiner may have to add a new hole for the lock or screw holes to attach the mechanism.
Lock types and prices do vary, but this should be an inexpensive job in terms of labour from your tradesman.
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