perfect approach!I think the focus in in the wrong place here. If the budget is 1k I would say you could make a really nice 1k-1.5k system. This will actually probally get louder and tighter than a 2k system because his vehicle won't handle 2k easily without an upgraded alternator. I would say first before you get all that speakers/subs/amps spend time planning electrical and dampening for a 1.5k system. Buy sound deadner at least, and if you want some MLV tiles or CCF. Spend hours deadening spot speakers are going, dampen trunk/reardeck/doors/sidewalls and cover holes well. Next layer MLV or CCF on top for more insulation/road noise reduction. Then lets get the electrical going, get 1/0 do the big 3 first Approx 5-7ft. Then get 1/0 and a nice second battery for the trunk. Run the 2 batteries together in parallel approx 30-40ft. Now that you've got your electrical and dampening needs fulfilled come back with a budget for patch cords/amps/head unit/speakers/subs.