I've managed to find one near me (funnily enough I think it was the one I test drove at the dealers before opting for nationwide who offered a cheaper deal).
2020 Cupra with less than 2000 miles for just under £25k.
Only worry I have is if they will let me arrive exchange my current car but also, if my finance application would be rejected since I've only just applied for finance a few weeks ago.
Edit - just phoned and of course being an idiot I didn't think that because it's technically not new they don't offer a lease for it. Oh well back go the drawing board!
Have you considered a PCP deal on it?
It's not leasing, but it's about as close as it gets. Lower monthly payments due to the balloon payment at the end, and if you don't want to buy it at the end of the term you just hand it back.
It's also easier to get out of a PCP deal than it is a lease should you ever need to get rid of the car. You can either sell it and settle the outstanding finance, or you can legally hand the car back with no fees once you've paid off 50% of your contract.
If you're dead set on leasing though then it's obviously not for you.