Sounds grim if it is an uneconomic repair.
Remember if it is on HP and not some other form of finance that if you have made more than half the payments you can just return the goods. If there is damage their may be issues.
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How to end your contract early
If your HP agreement is for under £25,000, you have two ways of ending it early:
• You can terminate an HP agreement and return the goods at any time by writing to the lender. Once you have terminated the agreement, you will need to make good any missed payments and then bring your total payments up to half the total amount payable under the agreement (the exact amount will be stated in a box on the front of your contract). But if you have already paid more than this amount, you will not receive a refund of the difference. In addition, you will also have to cover the cost of any damage to the goods, and pay off any credit you took out to pay for insurance. But you can’t be prevented from terminating because you haven’t yet made all of these payments. See our website for further details.
I have run bangers for most of my life. A friend bought a C5 and had no trouble with it I'm always wary of French cars in general and Citroens in particular. Not to say I havent owned Citroens.
At the moment if your doing a significant mileage a banger could cost more depending on it's economy or lack of.