I would not disagree with you at all. I can understand exactly how you feel.
If this was in the first 30 days, you could reject the goods/vehicle and get a full refund under the Consumer Rights Act. After 30 days your remedy is damages (another word for compensation). Compensation would be either the cost of putting the vehicle right or sum of money which could be up to the value of the car if it is not possible to put the vehicle right.
It is worthwhile mentioning that even though your statutory right within the first 30 days (I know this is after 30 days) is to reject the goods and get your money back, garages in particular do not normally roll over without a fight and refund £65,000 in full.
If you purchased the car on hire purchase, then liability for this rests not only with the garage but also with the hire purchase company.
For a claim brought within the first 6 months after purchase there is a presumption that the goods were faulty at the time of purchase. After six months, the onus is on you to prove that the goods were faulty at the time of purchase.
To bring a successful claim to recover the cost of the vehicle, if the garage will not pay up and simply want to repair it, you would have to prove using expert evidence that the integrity of the vehicle has been compromised and that regardless of how much work they do on it, it will never be as good as a new and repaired vehicle. Without that evidence, your claim for a full refund will fail.
I understand how annoyed and frustrated you are particularly in view of the value of the car but from a legal point of view it is the legal principle which is important not the amount of money which is in issue.
The first thing you need to get is the engineers report to confirm that the integrity of the roof has been compromised and that no amount of work can ever put that back. Once you have that, you can then move forward but if the garage will still not refund your money or replace the car, you will have no alternative but to go to court. At this stage, because you have only had the car for 2 months, I think you have a reasonable chance of getting a straight swap although that comes down to the garage. If they won’t, then your remedy will only be available through court although they may settle out of court to avoid incurring legal costs.
I cannot see how they can be anything other than liable, it’s just the amount of liability which is in issue. Incidentally, liability rests with the retail garage and any hire purchase company, not with the manufacturer.
Can I clarify anything for you?
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