I'm interested in purchasing a new car this summer in the ~20k range give or take a few grand. I was originally looking at cars like the Cobalt SS, Civic Si, VW GTI until I check the used market and saw that I could get some nice Z's, RX-8's, WRX's, etc. in that price range.

What does it take to keep a 350z running though? Obviously a Porsche costs more to own than a Chevy, so that's the type of comparison I'm looking for. Is there a significant difference in the cost to own a 350z compared to some of the other cars I was originally looking at? Are there any model years to steer away from? How is insurance on the Z? I know insurance will vary on age, location, etc. but a general idea would help.

...Can't think of anything else at the moment but if there's anything else I should watch out for please let me know. BTW for the insurance comparison I'm 20 in June and make between 15k to 25k per year. My income varies because I change my work hours depending on how my classes I take in college each semester.

 

Here's some of the cost involved with a 350Z that you may not have with other cars:

1) Better oil. Something like Royal Purple.
2) Tires. The Z burn the rears faster because you can't rotate.
3) Gas. Preimium only. At the rate prices are going it's going to hit you.
4) Insurance depending on your credit, record, age, and sex.

As of all mass produced cars, the Z has it's share of problems. Do a search for the TSBs:
Quick break down of major issues:

03-04 Tranny grind and tire feathering.
06 Rev Up motor oil consumption.