Somebody with the same name ! to the forum!
1) I'm fairly heavy footed and I typically get about 24-26MPG on a motorway run can get up to 32MPG
2) I understand that imports might have a higher premium on the insurance I'm sure there's other things but some of the experts should be able to help you further
3) Some of the 03-05 VQ35DE engines to consume oil and needing topping up every so often
4) Fuel obviously, tax (depending on what year/model), regular servicing costs. Mods, becauses eventually you will want to mod the car haha !
5) There is the 'clicky' rear axle which I believe is a simple fix with some grease, BOSE stereo sometimes skip CD's....maybe some others I can't remember. Other than that, fairly reliable cars.
Btw the search bar in top right is your friend for finding threads on info you need