buy one in warrany.
forgot mines had new maf this year ( i bought one as output was getting lower, so replaced it, Audi wouldnt do it under warranty as it wasnt throwing errors)
Coils should be ok, They are not expensive these days and a known (past) problem) so usually replaced free if failed , sometimes even out of warranty.
DV is cheap enough to replace, even if it was ok, for the cost, id replace it anyway if you intend to keep the plastic bosch one. Circa £15.
some people have complained of the rear washer squirter failing, ive never had this. Pipe comes off or shaft its pumped up through snaps.
sometimes coolant sensor plays up there is a revised one (my 2003 didnt have it ) it has now and is on latest green sensor. circa £25 diy fit.
this sensor if the old black one known to play up and throw errors. can affect performance and fueling as part of the decision process for the ecu. green version is the revised sensor.
watch out for aftermarket lowered suspension, Often puts out the geometry and causes wear on inside edges of the tyres. Usual trick to stiop this is fit adjustable tie bars to correct the problem, which adds extra money often not allowed for ontop of suspension changes.
Factory fitted Quattro GmbH doesnt need this. Perfect even tyre wear.