The warranty is somebody else's promise, and you are describing it

Say whose promise it is, in the first sentence

A manufacturer warranty, a dealer-backed scheme and a third-party policy behave differently when something fails, and buyers assume all three are the same thing. Naming which one is on the car costs a line and prevents the conversation where a customer explains that the dealership told them they were covered. The assistant describes the cover; it never stands behind it.

What voids it is the question nobody writes down

Servicing outside the schedule, a non-approved part, a missed stamp, a modification, mileage past a threshold: every scheme has its list and almost no dealership publishes it. That list is what the buyer is really asking about, because it is the only part of the warranty that can be taken away from them by something they do. Publishing it reads as honest and also removes the argument later.

Never say whether a specific fault will be covered

A claim is assessed on inspection, and the answer depends on cause rather than symptom. "That should be covered" is the sentence that turns a repair bill into a complaint about the dealership rather than about the scheme. The honest version is to describe what the cover includes in general, state that the decision follows an inspection, and say who makes it.

Aftersales is the part that is wholly yours

Service intervals, what a service includes, courtesy-car policy, how long a booking takes, whether a collection service exists: this is the dealership's own ground and it answers a different worry, which is what owning the car will be like. It is also the half a buyer is most likely to ask about after they have bought, which makes it the half that earns the next sale.