IMO its even more important you do shop around. I'm a bit confused as if you are buying privately or from a trader, as it sound like you are trading your current car?
just cos someone is giving you what you perceive to be a good deal on your current car, just to shift a high mileage car no one else wants (that by the sounds of it is over priced if moffspeed got that minter for under £10k) , time to take a second look and sell your clio privately and shop around.
also unsure what you mean it will owe you £7400, are you excluding the money your current car is worth?
2 years private warrenty = maybe pretty much worthless, read the small print, i bet it needs full VAG services, there will be some way that its void, esp on a high miler.
problem is i am doing a swap for my clio i dont actually have the physical cash to shop around!