Maintenance wise, its just rumours that Audis are hard to maintain. The bad reputation of Audis were actually cause by Auto Dunia back in year 2000 to 2002, during then, Audi Ingolstadt wanted Auto Dunia to set up a big Hangar which is estimated to cost RM30 million, however Auto Dunia wasn't willing as its a big investment, hence Audi Ingolstadt decides to cut off their distributorship, knowing this will happen, Auto Dunia slashes the price of A4 1.8T to RM155k, from RM220k; attracting many buyers, but the ugly thing is, they overcharged heavily on almost everything, for example a pair of rear headlamps which now costs RM 280 per piece, was charged for RM1600 per piece ! and there's even an aunt of my friend who by then bought the A4, went for routine service and the bill came out with
RM32,000 ! claiming they've changed a very critical part of her engine, when she doesn't want to pay, Auto Dunia suggested that they will pay half of the bill which is RM18,000 because the car is still under warranty (they claim that part wasn't under warranty). This kinda bullshit turns many consumer away from Audis since then.
Ok, sorry for the long story, maintenance wise, an A4 costs almost the same as any other Jap makes and German marques, its the parts that are slightly more expensive, parts are abundant, you can find almost everywhere. The thing about Audis is that, you cannot neglect the car, for example if oil change were to happen every 5000km, you have to change them by then, they weren't as crazy as local cars whereby you can ignore the 5000km thingy and change it at 7000km, and for timing belt change, thou they claim 120,000km per change, do it at around 90,000km if you aren't a hard driver, or change every 60,000km for optimum condition. Lastly, A4's control arm was made of aluminium, being light and agile, it weren't as robust as steel parts, cos Malaysian road conditions was slightly worst than country roads of germany (hehehe) so the wear and tear is quite obvious.
Lastly, i Audis are just like any BMWs or Volvos, rides comfortably, and very long lasting provided you service them periodically. oh, Audi's are made galvanised steel, wont rust !
p.s. Since you're intending to get some 20 yr + contis that costs around RM10k++ means you gonna pay cash right? Why not opt for a 96/97 Audi A6 C4 and get loan? RM30k+ with a 7 year loan wouldn't end up much per month right? then use the 10k you have to slowly service it part by part... then you'd get urself a relatively modern conti, and one that rides damn smooth ! good luck in ur buy friend !