if i have enough money to do only ONE of these, what do you guys think i should do first,i can't decide?

replace timing belt/water pump.

take car to dealer and have my cars problems finally figured out(throwing codes 22,41,16,running rich/slow)been trying to figure out code 22 for about 5 months.

get a nice pioneer amp and alpine sub/box for $250 total(christmas special on base-ends on the 22nd)normally $550.

get passenger side rear quater panel replaced-$1000(long story,sum1 ran into me and the whole panel looks so unbelivably horrible right now,allready had frame pulled back.

i have a 95 2door gsr with 86,000 miles.