We've had an '00 S4 since new and she's still ticking. On the brake/vacuum issue, please check to see if there is a vacuum pump located in the left (driver's side) fender well (forward of the tire). That's where they were from the factory and they and connected hoses failed often and with pretty disconcerting results if you were cruising at highway speeds and needed to stop (from personal, thank God, non-tragic experience). You will hear it running at start up when the engine is cold. There was a recall whereby the vacuum pump was relocated to a more protected location in the engine compartment. It is barely audible, if at all, in my experience. Be sure, for your kid's safety, that the recall work was done.

Haynes manual from the UK is the only manual for this car I have ever heard of or seen. It's barely adequate for most "shade tree" tasks. You can order from Amazon UK or other UK online bookseller, I think. That's how I got mine. There is great info on this forum and on other Volvo sites, like Volvospeed (look for Bay 13), and Matthew's Volvo site. Sorry, I don't have the links handy, but google and this forum are your best friends. You'll find that there is a remarkable similarity between the mechanics of the 1st gen. s40 and later 850s--just one less cylinder and less room to move around the engine.

Expect short headlight life and rear brake pad life. The former is a glitch that another recall (some different wiring harness parts--I never dug into exactly what it was) did not fix on my car. The latter is due to brake pressure balancing which shifts more braking to the rear than most cars would--it makes the car very safe and stable in hard braking, but eats the too-little rear pads. I got about 12k miles out of oem pads and maybe 50% more out of good quality aftermarkets (mintex). Intended to try EBC green or red stuff, but just never have--cost was an issue.

As said, we've had her since new--considered getting rid of her a few times, but never found anything we really wanted enough more to pay for it. She's got character, nice performance and reasonable durability. Hope your daughter enjoys hers as much as we've enjoyed ours.