Dad said you may have a way into the house. Good. That is permission for a job, not permission to redesign his front door while he is making coffee.
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The cost question is not simply what one key costs. You are choosing a small access system: which door opens, who can use it, where the key stays, how permission ends, and what happens when somebody loses a copy. Set those terms first. Otherwise the low-cost answer today can become a locksmith call, a new set of locks, and an argument about who was allowed inside.
Price the problem you are actually solving
Ask Dad what event this key is for. A scheduled visit is different from a fall, a missed phone call, or a door that locks behind him while he takes out the trash. Then walk the intended route with him.
Check the outside gate, storm door, main door, interior alarm, deadbolt, and any door that swells or sticks. A key to the knob does not help when the deadbolt is set. A code to the garage does not help during a power failure if there is no usable manual entry. A back-door key is no bargain if the route requires wet steps and a dark yard.
The National Institute on Aging tells families to examine whether a home is safe and accessible and to identify what help the older adult actually needs. That same discipline belongs here: test the whole route, not the object in your hand. The source is cataloged on the site’s Sources page.
Compare four kinds of cost
A plain duplicate usually asks the least of the hardware. It works when the lock operates cleanly, Dad knows every existing copy, and one trusted person needs access. Ask whether the key is marked against duplication, whether the original is worn, and whether the duplicate will be cut from a clean original rather than another copy. Test it from both sides of the locked door before calling the job finished.
A rekey keeps compatible lock hardware but changes which key operates it. It can make sense when Dad does not know who holds old copies, a helper has left, or a key is missing. The quote should state every cylinder included, the number of working copies returned, whether all selected doors will use one key, and whether damaged hardware is outside the price.
A lock replacement changes the hardware. That may be necessary when the existing lock binds, the door and frame do not line up, or the hardware cannot be rekeyed as intended. This is where the bill grows quietly. Ask whether the price includes matching the existing holes, adjusting the strike, repairing the door, keying multiple locks alike, and hauling away the old hardware. A new lock installed on a dragging door is still a dragging door.
A keypad or lockbox trades key handling for code handling. Price the mounting work, batteries if used, weather exposure, code changes, backup entry, and removal later. Ask what happens when the device loses power, freezes, jams, or is entered incorrectly several times. Also ask who will know the code and who will change it after a helper, contractor, or neighbor no longer needs access.
Make every quote cover the same door
Do not compare one locksmith’s rekey price with another locksmith’s full replacement price and call the lower number a win. Give each provider the same written scope: address, entry door, number and type of locks, desired number of keys, whether locks should share one key, condition of the door, and whether emergency or after-hours service is being requested.
Ask for labor, hardware, service call, additional-key, and after-hours charges to be identified separately. Ask what can change the total after arrival. If the provider cannot describe the hardware without seeing it, send clear photographs of both sides of the door, the edge of the door, and the strike in the frame. Photographs will not settle every question, but they make vague estimates work harder.
Federal Trade Commission guidance for home work says a written estimate should identify the work, materials, completion terms, and price, and recommends comparing multiple estimates. That guidance is listed through this desk’s source record. For this job, add one more line: no drilling, replacement, or added hardware without Dad’s approval.
Keep the legal line visible
A key is access. It is not ownership, a power of attorney, permission to search papers, or standing permission to enter whenever Dad does not answer quickly enough. Write down the narrower agreement in ordinary language: who may enter, for what reason, whether they should call first, and whether they may give the key or code to anyone else.
If Dad rents, lives in a condominium, or has an association-controlled exterior door, check the lease, building rules, and management procedure before changing hardware or mounting a lockbox. Ask who owns the lock, whether management needs a copy, and who pays to restore the door. Do not let a locksmith discover the building rule with a drill already in hand.
If several relatives want access, Dad should name the people himself. More copies can lower the chance that no one is available, but every copy creates another loss point. A simple key log works: holder, door, date issued, and date returned. Do not write the street address on the tag.
Price the exit before choosing the entry
Every access plan needs a cheap way to end. A duplicate key may require collecting copies or rekeying. A keypad may allow a code change, but only if somebody knows how to administer it. A lockbox can be removed, but removal may leave holes or damage. Put the exit step beside the purchase decision.
Ask Dad what should happen if a key disappears. Decide who calls the locksmith, which doors must be changed, and who tells the other key holders. If a code is shared temporarily, record who received it and change it when the job ends. The point is not surveillance. The point is avoiding the family classic in which everybody thought somebody else had collected the key.
Do the door test tonight
With Dad present and agreeing, choose the one entry door that is safest and most dependable. Lock it exactly as he normally does. Have the intended helper enter using the proposed key or code, disarm anything that must be disarmed, and lock the house again on departure. Then write down three things: who has access, what permits entry, and what event ends that permission.
If the route fails, photograph the lock and door edge and request like-for-like written scopes from two locksmiths. If the route works, label the key without the address and put it in the place Dad approved. That is the next move tonight.