Taking the plunge

I have a 98 Jetta GLX (a stepup from my 94 GL) and now I have decided to take the plunge and go to the 2001 GLX. I am looking at adding the sport suspension, in dash cd, and cd changer, splash guards, floor mats, and air guard for the sunroof/windows amd read spoiler (want to deck the car out). Any idea of what a reasonable price would be for this? I know this is a pretty generic question, and I can see the MSRP and dealer invoice on the net, but what is the demand for this car? Will I have lots/some/any/no negotiation ability on it? And lastly, are the 2001's out in volume at the dealerships? I will be trading in my 98 with 38k on it, and an upgraded in dash cd w/cd changer in the trunk, any ideas of what you think a dealership may give me for my trade in?