Label each number
A registration number and a vehicle identification number serve different purposes. In your viewing notes, give each its own labelled field. Do not store one under a heading intended for the other. This simple distinction is useful when a seller sends several photographs or when you are comparing multiple vehicles.
Do not infer equipment from a plate
The appearance of a registration plate does not establish which seats, lights, audio system or driver assistance features are fitted. Use it to identify the vehicle being discussed, then check the equipment separately. If a registration lookup returns a VIN, compare that number with the vehicle and its documents before relying on it.
Keep photographs in context
When saving a listing, keep the date and listing reference with your notes. Avoid placing a plate photograph from one car beside the equipment list of another. If a seller has several similar cars, ask them to identify which car each photograph shows.
Use a clear enquiry
Send a short enquiry with separately labelled identifiers and the particular feature you want to confirm. If you only have one identifier, say so rather than filling in the missing field with a guess. When the reply arrives, check that it refers to the same vehicle. A useful response should answer your equipment question as well as identify the car.