If paying for a car at a dealership in the uk, are you charged extra if you pay with a card?

I.e. credit or debit card? and do traders offer any kind of discounts if you pay in cash? and what are the trader/dealerships preferred method of payment and why? thanks!
Answer
A trader can charge you more for buying nices with a credit card than if you pay by cash or cheque. to be legal, a trader who does this must display a notice in the shop saying this, and the price differences.in practice they get around it by offering a discount for cash instead.they normally prefer you to sign up to their own partners credit agreement as they receive a cut (and will try to slip in expensive unwanted extras like payment protection).