amp question

[dmbfancb]

my band is trying to decide on an acoustic amp, right now we have a mic and an a/e guitar going through a mixer and from that into an electric guitar amp. first, we are on tight budgets. we are thinking about monitors but would it be wiser and/or cheaper to go with powered monitors instead of a power amp/monitors, and would the sound of the guitar and vocals be any clearer and crisper with the guitar to the acoustic amp, and the amp to the mixer through the monitors also if we went with powered monitors, would we need speaker cable from the mixer or just regular line cables thank you