Problems associated with turbo's?

Im looking to buy a 96-2000 civic EX... figuring it will have in the neighborhood of 50,000 miles on it, i was wondering what kind of problems i could run into with a turbo. Does it have any negative effects on your motor? such as shorter life, more wear and tear etc... what other mods would i need going to a turbo as far as a clutch handling around another 60-70 horses of power? Is there any additional maintinance associated with turbos? any info is appreciated.
Derock