Sterling has collapsed against the Euro (and most other currencies). Spanish horse traders have sewn up the used market in the south. They are the only people who can buy at auction and they add a 30% + profit margin to anything they buy. The other factor comes from translating UK prices to Euro prices. Though new and used prices have been going up, UK used prices remain much lower than in continental Europe. But there is no way that converting a RHD car to LHD is economically viable, and the car would not then meet Type Approval. Buying LHD in the UK is dear because unless they are UK distress sales the cars have to be sourced from the much dearer Euro market. In Spain, the process of certificating and registering a car from another country is a nightmare, even if your Spanish is fluent. And you cannot now register a car in Spain unless you are resident there for tax purposes on your entire world income.