Car Import from UK

I bought a UK car in January 2019(I arrived permanently in 2021) which I drove to France in but shortly after arriving it broke down & we just abandoned it at the bottom of the garden. Given the price of 2nd hand cars now we want to explore the possibility of registering it here. Obviously we should have done it years ago but can anyone envisage any problems? The exemption was only for 6 months I think. It’s old & I only paid £2K for it then, how do they arrive at the figure for any duty/tax that needs to be paid? Do they value it or is it calculated on the price you paid? If it’s too high then we wouldn’t bother. Many thanks.

As far as the French authorities are concerned it only matters from the day you bring it in for registration . That it was hiding in your garden for years does not matter to them* . So assuming the car was 2019 new and you want to register it in 2027, it is an 8 year old car that you are importing today. They will look at the price that car in France or a close equivalent and the cost in 2019 ,and calculate the depreciation and that is the value of the asset you are importing.
* That could matter to the traffic police , except fortunately they don’t know about it , because any car has to be insured ,whether on the road or even on private land and even if it is not roadworthy or working. The principle is that if it could be stolen ,it could cause an accident and someone Injured . It is the car which causes the injury ,not the driver.

There are two steps . Registration of the car including paying for it’s importation .That will supply number plates . And then it would need garage certification that it was roadworthy for French roads

The cost will easily be in the 000’s - a Certificate of Conformity (if you don’t have one) is 100E upwards, if it’s a high powered car the “horsepower tax” could be up to 400E, the MOT (CT) is up to 90E and the processing fee is around 80E. Add in any repair costs to get it roadworthy and it may well cost way more than it’s worth.

If the car broke down 5yrs ago, why wasn’t it repaired then? What was the breakdown?
5yrs stood in the garden? In wet grass, or on dry gravel?
Apart from repair to whatever the breakdown issue was, look at brakes, exhaust, etc for rust.
Battery likely shot.
Look at the condition of tyres especially if exposed to strong sun. There is no legal age limit on tyres for UK and Fr cars but 10 years is considered old.