I would go on line and google citizen advice and go on to .gov web sites for your right for not to buy and get your money back.

Did you sign a contract for which the small print is on the same document.

You don’t have to buy the car, but your chances of getting your money back are slim.

Ive taken dozens of deposits on cars Ive sold over the years. Each said and was "non-refundable" and I made sure each buyer knew exactly what it meant, that I was taking the car "off the market" in exchange for their deposit.

I only had one pissed off lady and I told her she could get $100 off ANY other car I had or would later get after she changed her mind but I wouldn’t give her the money back.

I don’t know what "stroppy" means but I wouldn’t give your deposit back no matter what you did short of pointing a gun at me.

Why ? Dealers are in business to make money. Taking a car off the market in exchange for a deposit that is refundable if the buyer changes their mind is a losing situation. One no dealer will put themselves in.

The dealer can lose a sale because your car is "sold" and he would be out however much his profit is. which is usually much more than the deposit.

Now, some of the bigger new car dealers might give your money back, but none of the independent or smaller guys.

Its the same as them opening up their wallet and giving you money for free.
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Now, IF and only if, the deal was subject to bank financing, you could say you lost your job or something, in that case, the bank wouldnt approve you and you would get your deposit back.

However, some garages might consider cancelling the agreement and returning the money, but they certainly don’t have to. You might have to lie to them about some family crisis, but be aware they’ve heard this before.