I didn't realise the charges involved, unfortunately it's a bit of a minefield if you go down the import route. You mention worrying about the car's depreciation if you opt for this car which is currently on 82k miles. Even if you stay within a modest 4k miles per year, then you're going to get to around 100k miles in 4½ years, but by then the car will be over 23 years old. At the end of the day - you're over-thinking this. You're buying a performance car, and it will require servicing and spare parts while you own it, plus insurance, road tax, etc. It is what it is. I don't think you can realistically guarantee a future value, short of sealing it in an air conditioned garage on axle stands. If you were thinking of a physical investment, you could potentially go down the B5 RS4 Avant route. That said - there's a mint example on Autotrader under 20k miles finished in Avus Silver. That's never going to be realistically driven and will probably spend the rest of it's life trailered to car shows, plus it's £70k. Best of luck of luck though whatever you do.