Myself and my band (Guitar, vocal, bass and drums) are looking to get gigging and want to do it using just amps insted of a PA for better sound and lower cost.

I as guitarist will be using my marshall 100watt head through a 4x12 and keeping the volume down, i know the drummer wont need amplification but do you think amps will be enough for vocals and bass?

At the moment we're only looking at little pubs and clubs, and with any luck some will have house PA's but for those that dont what would you recoment as the minimum size amp for vocals and bass.

Hope i was clear enough
my band used a bass amp for vocals for awhile, and it was ok for practice and with 2 bass amps was ok for house parties. we eventually started renting a pa from a guy for $50 whenever we had a show and it made a big difference. it wasn't a great pa. 2 speakers, a mixer, and some mics. i think you should mic at a minimum- vocals and kick drum. that's the bare bare minimum.