to DTMPower!
Let me try to answer your questions...
1. Tires need to be replaced quite a bit and they're not cheap.
2. Aftermarket performance parts are expensive. A simple muffler ranges from $1200-6000 depending on materials and marketing.
3. Service is dependent upon your local dealership. But just realize that Inspection I is roughly 1200-1500 and Inspection II is 1600-200. Oil changes you can do yourself.