im going to try to do this without giving you too much of a hard time, you can get an audioque hdc 18 and a used bxi 2000 for just the price of the solo x itll "wang" just as hard, probably hit the lows better and sound better and be equally impressive cuz instead of people going "oh its a solo x thats why its loud" they'll go "WTF is that?!?.. and where can i get one"
and i know your probably unfamiliar with audioque...
http://www.audioque.com/aq/HDCSeries.htm
http://www.caraudio.com/forum/showthread.php?t=375950
so 345 for the sub, 200 for the amp, your GOING TO NEED a battery with that little car, yellow top up front and a deka 9a31 out back will probably be sufficient. bout 100 for the yellow top and 150 for the deka. also going to need approx 50ft(guessing, 17 from front to back, 3 for ground from amp, 3 for ground from 2nd battery, give or take 15 for big 3, 5 from second bat to amp... and a little extra) of 1/0 power cable for big 3 and for amp powering.
http://www.knukonceptz.com/productMaster.cfm?category=KLMX%20Kable 1.75/ft unless you can find it cheaper on the boards.
so lets total it up.
sub - 345
amp - 200
yellow top - 100
deka intimidator 9a31 - 150
wiring - 100ish
terminals/fuse holder/fuses ETC - 100ish
wood - 60ish (going to probably need 2 sheets, 4.5 cubes @ 38hz...72 in^2 port)
so... grand total 1055$.... approx. my suggestion would be to give someone on here your max dimensions for the box, have them design you a box down to the size of each panel, go to home depot and have the guy runnin the panel saw cut your box out for you, all you gotta do is glue n screw, like putting a puzzle together. don't forget to brace