Welkom along
My advise would be if you plan to keep the car standard, buy at the top of your budget and enjoy a newer car. If planning upgrades ie engine, suspension, tyres, brakes etc retain a couple grand to comfortably allow for these.
350z engines are irrc:
276bhp DE
296bhp DE RevUp
308bhp HR
Some folks say tax bracket doesn't matter, and yet almost every ad both on the forum and Autotrader etc emphasize 'cheaper tax' for DE models so take from that what you will.