Hi all.. new to the forums so go easy!

I'm really considering buying an Audi A3, love the look of the car and as it will be my second car I'm looking forward to having a powerful/fun car for my daily commute to work (currently have a 1.2 corsa).

I have been plowing through Autotrader on a daily basis and have come across a few ones I'm interested it, but as I haven't the best of knowledge with audis, I'm here to ask for peoples advice.

One ive been looking at here

What should I be looking for when viewing A3's?
What kind of problems are common? (From googling about I've read things about the injectors being problematic).

If people can simply offer their wisdom it would be greatly appreciated!