HI Mark,
the ABH engines are a bit infamous for burning oil - sometimes more than a gallon per 1000 miles. Keep an eye on the consumption - if it's below two liter a 1000 miles, it makes sense to overhaul the heads. If it takes significantly more, save the money, let it burn. Something more serious and in most cases irreversable causes the oil burning.
The ABH are as well famous for blowing the head gasket on the back end of the left head and the front end of the right end. Take a look on the alternator, it is probably already oily. In both cases chaning the head gasket is the only way to go.
If you plan to replace the vavle seals, it is highly recommended to clean and refit the valves as well, 'cause in most cases oil carbon has already settled on them, wearing your new seals out in no time. A look inside one of the cylinders (probably the one with the most oil carbon on the spark plug) with an endoscope could give you a hint about the need of a vavle refit. Maybe taking away the heads becomes a requirement anyways.
In your case I would visit your local Audi dealer and gently ask for the tools required for pressing downholder of the valve springs - they may have the timing belt tools as well for a box of beers
Maybe I meet the trouble halfway, but experiences told me that oil leaks and consumption on the ABH are often a never-ending or at least enerving story. As you seldomly stress the engines in the UK due to strong speed limits, chances are good that you don't have that much troubles as we have 'em on some engines over here. But still you should be careful to not spend money for nothing.
Good luck
Bastian
