So what is it that you are actually attempting to accomplish? Try breaking down your sentences a little better so the rest of can understand what you are wanting. We are ALL willing to help out, just be realistic. Prices are expensive for the RX-8 because there is not much aftermarket support for a high numbered build. It is however very common to make it into a "spirited" car.

My suggestions would be as follows:
-full suspension
-bracing
-wheels and tires
-upgraded flywheel and clutch
-intake/header/exhaust

Learn what the car has to offer you with simple bolt on modifications. The car already has decent handling from the factory, the above mods will make it a bit more fun and reliable.
The Greddy kit is decent, but if you are going to buy any kit it will be around 3-4k. If you want to build a basic kit and run 7psi then you should be fine and it could be had for around 1k.

everything said was in good fun, this is how the mazda family works on here. you will fit in just fine. Good luck with your build and make sure to keep us updated with your progress.