Buy a new one and use the £3500 to make the repayments and a bit of deposit. Most Fiat dealers have a car for less that £6000 hidden somewhere and then you don't have to worry about the MOT for 3 years. Also shouldn't have to fix anything for a while I saved a fortune buying my fiat New Years ago and will be doing it again as soon as I can afford it. Spent more on the wife's punto in the 2 years we've had that than on my Seicento in the first 8 years until I killed the gearbox not putting oil in it. Still as I've now fixed most things on the punto will keep that for a while pretty nippy for a 1.2 auto when you get used to it