Reply to Sound System for a New DJ

Hi all, i had my first gig last evening and it was off the hook! Everyone loved it and today I am being congratulated and thanked left and right.

Aside from that, I already have a couple gigs being offered to me... the only issue I face is that I do not own a sound system.

What is a good sound system that's not too pricey (maybe available on craigslist / ebay)... that is powerful enough to play for a large school (high school/middle school) dance?

Tom

P.S. the sound system used last evening was rented. it cost $350. i would like to be able to offer cheap prices, but $350 is a lot, not even including an income for me.