From the shop on 1st Ave
Straight answers on locks, keys, and doors from the shop at 1450 1st Ave on the Upper East Side.
You do not know who still holds keys to your new front door. A locksmith's plain checklist for the first week in a prewar Manhattan apartment.
Anyone can copy a standard key at any kiosk. A restricted keyway changes that arithmetic, and it is why managed buildings keep adopting them.