A lock problem usually arrives as a small complaint: the key sticks, the bolt drags, or a neighbor mentions they got in with a spare. You can handle most of the decision from your phone, as long as you know which of three jobs you are looking at.

Local option: New Plan Care gives families in the St. Louis area in-home help so a parent can stay home: companionship, help with bathing and dressing, meals, and overnight care. Call (314) 405-0887.

Start with what is on the door

Photograph the lock from the inside and the outside, and photograph the edge of the door where the bolt meets the frame. Note whether the lock is a deadbolt, a knob with a separate deadbolt, or an electronic unit with a keypad. Count the keys that open it today. Those photos are the first thing any helper will ask for, and they save a second visit.

When rekeying is enough

Rekeying changes the internal pins so old keys stop working and new keys fit. It makes sense when the lock still turns smoothly, the bolt throws fully, and the only concern is who has keys. Not every lock can be rekeyed, so ask the helper to confirm that before any work is ordered.

When the lock itself needs replacing

Replacement makes sense when the mechanism is worn, sticks, or does not throw the bolt fully. Measure before you buy anything: the door thickness, the diameter of the bore hole, and the distance from the door edge to the center of that hole. A new lock that does not match those numbers will not fit, and an electronic lock adds a power or battery question that someone has to own.

When the door or frame is the real problem

If the strike plate is loose, the frame is split, or the door drags, a new lock alone will not secure the entry. Look for wood that has pulled away around the plate, screws that spin in place, or a gap that opens when you push. Those are door repairs, and they belong with a local helper who can look at the frame in person.

Who holds the keys

List every person with a key: the parent, you, a neighbor, a sitter, any contractor who has worked on the house, and any building or management office. Decide which of them should keep one. A rekey can take the list down to the people you choose, but only if the list is written down first.

Questions to ask a locksmith before they arrive

Ask whether they rekey on site or need to take the lock away. Ask what they need to see to confirm they are working for the home owner or the person who manages it, and ask them to confirm that in writing. Ask whether the written bill will list the number of keys delivered and the cylinders changed. Keep the bill with the folder.

What to do tonight

Send the photos to the parent's trusted local contact or to a helper you have already vetted, and ask for a plain answer on rekey, replace, or door repair. Make your own list of key holders and send it to the same person. If you want local options to check, our Local Help for a St. Louis Parent page is a starting point.

What to leave with the doctor

If the parent's grip, balance, or hand coordination is changing and a key is becoming hard to use, ask the doctor's office for a short note describing the change in plain words. Give the note to whoever installs the lock. It tells them what has changed in the person, not which product to buy, and it lets the lock choice match the real need.