All hail the mighty quattro!
I have the free vagcom shareware on my laptop, plus an ebay cable. Works well for home diagnostics. Although I will say this, although you may find fault codes appearing on your car, this is not a definate answer to all problems, can end up replacing all sorts of parts and not really solving problems, these cars are full of sensitive sensors and throw codes at the slightest sign of a fault, but not necessarily menaing there,s a serious problem. Ended up making me overly paranoid about my motor! Oh my god, there's a fault! It's all broken, gonna cost me a fortune! Sometimes best just not knowing, if you know what I mean!