so far about 3-4K easily, only had the car for a year..selling the car at the end of the year.

HIDS- $400
amber corners- $50
vis hood $300
carbon fiber mirrors..$150
rims $400
tires $250
agx--dont remember
neuspeed race springs $140
and so on....

edit
ill add more.
body work.. $-100 or less, did it myself.
paint $150 for paint, clear, hardner
paintjob - gave the guy $50 for booth and had my boy paint it.
oem style fogs $80
clutch $110 i installed it
red/clears - $90 sold for $25/oems