I know i said it before and people argued, but a UK car is dropping quick in money. At moment there is a Base model 04 listed on Autotrader for £16995, UK car, chilli red, still has Nissan warranty etc etc.
Now imo if its listed at £16995, £16500 will buy it if you land at door with cash. Now each to their own, and i've looked at a stack of imports while looking for a Z, but to me a UK car is making more and more sense.
Good luck with hunt
Aaron
EDIt:- Obviously i'd recommend all checks etc that you would do with any second hand car from a private dealer, but i only used that car to illustrate point. There are loads more springing up around that money, 2 orange ones GTpack/03/ and they are listed at approx 17500.