Start with what you still have
Do you have one working key, a damaged key, only a remote or no key at all? That difference matters when discussing the work. A spare-key request is easier to describe when the remaining key can be identified. If all keys are missing, say that clearly at the start. If your keys are simply locked in the car, begin with the vehicle-access discussion so the request matches the actual problem.
A blade and an electronic key do different jobs
A mechanical blade, a transponder key and a proximity fob can involve different requirements. A key that physically fits is not necessarily ready to start the vehicle. Remote buttons may also be a separate part of the issue you are describing. Explain how the previous key was used, including whether the vehicle has push-button start. Ask which functions would be included in a proposed replacement and how support is confirmed for your model.
Prepare the details before buying a part
Keep the year, make and model together with any information you already have about the key. Avoid buying a remote solely because its case looks right. Compatibility can depend on more than the visible shell, and parts supplied by a customer need discussing first. Tell us whether the vehicle is available at your home, workplace or another location, and ask what proof of ownership and access will be needed.
Make the estimate specific to the outcome
Ask whether the estimate includes the relevant key, any cutting or programming that is required and the functions you expect to use. Confirm the number of working keys to be supplied. If the missing key raises a concern about continued vehicle access, mention that separately and ask what options can be supported. Availability, timing and the appropriate process should all be confirmed before you make arrangements around the vehicle.