From what I can make of it, they look at what you need in a car to make it accessible for your disability. For instance if you need an electric tailgate or an automatic and reversing camera etc they allow for it. As AP are usually higher on cars like this. They take into account your income and do a means test if you don’t get income related benefits. They then tell you what level grant you have and what elements of the car it’s for and you can go and look for that and hand the dealer the grant letter so they know the grants team if paying that portion of the advanced payment or for the adaptions required. It’s a simple process really just fill in a form and send the evidence giving as much information as to why you need the aspects of the car you are looking for. They are very nice and helpful and not judgemental at all so worth giving a call.