My band is just starting to get some gear together for gigging and we are looking at ways of amping our vocals, how could we affordabye amp vocals to compete with 2 150 watt guitar amps, 300 watts of bass and a drummer?

a cheep PA system ?
My Gear:
Jay Turser Warlock
Baraccuda Strat
Takamine EG523SC
Samick Acoustic
Vox AD50VT
Boss DS-1
Boss CS-3
Dunlop Crybaby Wah
PA system
Fender American Standard Stratocaster
Ibanez TS-9
EHX Big Muff Pi
Companion Fuzz Box
EHX Pulsar
Boss DD-6
Fender Hot Rod Deville 212
I guess theres no other viable alternative then? How much is a "cheap" Pa system gonna set us back then? :P