Soldato
As it uses the 5G tronic, check that it changes gears properly up and down - noises when changing from P to D when cold are common but nothing to be too concerned about. Thankfully these older boxes are cheaper and easier to repair than the later 7G tronic due to a different valve body design.
Try and get a look at the front suspension in particular - these cars are old now so it'll likely be needing new drop links, new control arms, etc if they haven't been done already and it's been driven hard. Check the engine and gearbox mounts for noise too (you can easily tell the gearbox mount has gone if there's lots of vibration through the cars interior) as they wear quickly.
Otherwise you're buying on condition and general impression and I'd be expecting FMBSH up to a certain point and then MB specialist at least. Don't buy one at the top of your budget and then expect to not have to pay anything else - you'll likely end up spending at least £1k sorting small problems out on it, potentially more purely because of the age of these now.
