What he said, be prepared to fork out lots for maintenance. Also remember to get a bargain one, because you'll need the extra cash, things break fast because of the age.
You can also get a well maintained one (lots of stuff replaced) but be prepared to pay a premium. Bigger turbos, and new suspension doesn't mean well maintained. What i mean is, no leaks, new slave/master cylinders, replaced bushings, mounts hoses etc.
if you buy one under 20k. Have another 10k for replacement parts.
I think even the 33's are becoming of age now, 34 would be a much safer investment.
Having said that, I love my R32 and haven't looked back since.
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