Three situations, different information
If the key is visible inside a locked car, say where it is and whether another working key exists. If it has gone missing, explain whether you can access the vehicle at all. Those details help distinguish an access request from a request involving a replacement key or remote.
A key that is still in your hand needs its own description. Tell the person handling your call whether the buttons, the door function or the starting function has changed. A remote that does not respond does not by itself explain the cause, so keep the description focused on what happened.
The parked car is the destination
Blue Hills covers more than one municipality, and a trail or summit name is not a precise vehicle location. Give the road, named parking area and nearest useful entrance you can identify. If you visited Great Blue Hill, describe where the car remains parked rather than your position on the walk.
For a vehicle near Milton Village or Central Avenue, add the street number or parking entrance and a simple description of the car. Say whether it is in an open lot, private driveway or controlled garage. Mention any access restriction early so the request can be assessed with that in mind.
Make the next decision with clear details
You do not need to guess the vehicle's key technology. Its year, make and model, together with a description of the key and any remaining spare, provide a practical starting point. Ask whether that particular vehicle and problem are supported before you agree to a visit or other next step.
Ask what ownership or authorization information will be required and what the quoted work includes. Wait in a safe place while arrangements are discussed, and keep someone informed if you need to move away from the vehicle. If someone is in immediate danger inside it, contact emergency services first.
BEFORE YOU ARRANGE WORK
A few useful answers.
Is getting into the car the same as replacing its key?
No. Access concerns a locked vehicle, while replacement concerns obtaining a working key. You may need one or both. Explain whether the existing key is inside, missing or damaged so the request can be discussed in the right order.
Can I use Blue Hills as my location?
Use it as a reference, then provide the actual road and parking area where the vehicle is located. The reservation crosses municipal boundaries. A trail name or a summit location alone may not identify an entrance someone can reach by vehicle.
What if I do not know what kind of key I have?
Describe what you use: a metal key, a key with buttons or a separate fob, for example. Add the vehicle's year, make and model. Compatibility should be checked from those details rather than assumed from the key's general appearance.