the 2.0 is good out the box (kept within reason mods wise of course), 2002 onwards they don't have proper forged pistons, they use heated treated cast, but they are about 200000000000 miles better than the 2.5 out the box. (04 and 05 engines are pretty much exactly the same, 06 they shifted to the 2.5)
Keep on top of maintenance and they are reliable even with some modding.
One thing to bear in mind is your talking about a 20 year old car that was about £30k new to buy, so come service time bills will cost what they cost for a 30k car. Also at that age, it's highly likley it has wear and tare so will prob need some work. Rubber seal, bush's etc are the same on any car for example.
I'm not trying to put you off by the way, just trying to make sure you dont get any nasty surprises, they are amazing cars and tbh very little out there compares to them performance and fun to drive, i've had them for over 20 years now and even an M3 didnt come close to the enjoyment. With a scoobs its MOS not MPG, miles of smyles 😄