Hi Bradley
Obviously, budget is the thing. I paid a bit over the odds a year ago for mine but it was immaculate.
Make sure the DSG box is in good working order, my A3 is 10 yrs old now , it had a cambelt change at 70000 (now at 84000) & is completely rust free with everything working perfectly so far. including the hood which is down on every rain free day.
Good tips from Steve, just make sure you see full service history.
happy hunting