[Perfectlap]

you can get glass from the aftermarket for about $1000-$1300 installed.
Getting more power will cost you allot more.

But this should not be the only factors you consider. Mileage, service history, exterior/interior wear, are as important.

If all things are roughly the same between the 03 and 02 S,
I wouldn't hesitate in getting the S. You'll end up 2nd guessing
yourself forever if you don't get the S. You don't need that.