Separate the unit from the building
A private front door, lobby entrance and shared garage doorway can sit along the same route home. They need separate descriptions. If you rent, check with the owner or manager before a lock change is arranged. In a condominium, identify the person responsible for the particular entrance. Being able to use a door does not necessarily mean you can approve changes to it.
Choose between key control and repair
If the hardware works but an old key is unaccounted for, discuss changing the operating key. If a handle droops or the bolt will not engage, explain the symptom. A new key arrangement will not straighten a door or correct every worn component. You can ask about both goals, but keeping them distinct makes the proposed work easier to understand.
Build a small list of entrances
Include every private keyed entrance you want considered, rather than treating the property as one lock. Note which keys currently work where and whether a working spare remains. If fewer keys on your ring would help, say so early; compatible cylinders may allow options that visually similar locks do not. Describe any handle or finish you hope to retain before buying parts.
Check the result you asked for
Before approving work, confirm which locks are included and how many usable keys you need. Ask for a demonstration of the agreed result with the door in ordinary use, not just a key turning in isolation. The estimate discussion should account for parts, keys and any separate fault. Keep the finished key set organized so a forgotten entrance does not remain outside the plan.