(Original post by 1992LP)
First off, VAG = Volkswagen Audi Group. Seat, VW, Skoda, and Audi are all the same company, and all the cars have the same basic platform and engines / running gear.
The Fabia that you are looking at shares the same platform and engine as the Polo and Ibiza. A good start, if all you are looking for is a reliable comfortable car to get you from A to B - there is nothing wrong with them at all.
IIRC the 1.2 is a 3 cylinder engine, so don't expect much performance. If you can, I would seriously consider a 1.4 or a 1.6 as the fuel consumption will be pretty much the same (small engine, heavy car = working hard all the time = uses a lot of fuel) but I appreciate that the insurance may not be so friendly.
There are some quality control issues with the new Fabia (Skoda use cheaper materials than VW, but the cars cost less) so make sure everything works as it should. It is basically a new car so it should not be showing any signs of wear.
You say you are spending £6.5k on it, that is a huge sum of money for your first car IMO. I would also consider spending less (around £2k) on something like a 1.6 Focus and saving the rest until you can afford to insure a really nice car. Remember it will depreciate a lot since it is fairly new so come resale time in a year or two it will be worth considerably less.
Either way, it is your money, so you can do whatever you like with it! It is not what I would do, but everyone is different. Good luck with whatever you decide on, and quote me if you need anything else
ETA - I have done some research on the 1.2 3cyl engine, and it appears that it is an old design carried over from the early 2000s Polos, and has some issues. The major one of snapping timing chains due to poor lubrication has been cured thankfully, but there are several reports of axillary drive belt failures, issues with EGR valves and burnt out exhaust valves (it is thought that they need higher octane petrol to operate at a lower temperature?).
No major issues, but tread carefully. If it doesn't check out, and it MUST have a full service history, then walk away. Good luck!