Budget is 2-3k. Is that too low? I don't think we need 10-15k for what we are doing.
Depends on the quality you expect, how much of the band you plan to mic, and what your future goals are. If we are talking new, this budget will get you an entry level system that will push vocals only. If everyone has a decent amp you can easily do small bars with this type of setup and sound respectably good. I am talking powered mixer, four speakers, four crappy mics, cables, stands etc. Many people would be happy with this type of system....In my opinion you start out with yuck and there is little you can do to improve or expand it! You can however, do far worse by spending even less.
Here's what I would buy. These are fairly common Ebay prices: used Yamaha O1V 96 ($1000 each), used 1 QSX PLX 3002 ($500 each), three new Audix OM5s with crappy stands and cables ($477 for the kit), four used EV SX300 ($5-600 per pair...two for mains, two for monitors). Ooops already spent $3000 and haven't bought speaker stands, speaker and power cables, racks, direct boxes, etc. However, this system will blow the system above out of the water both quality and volume wise and can be upgraded with extra power amps, subs, crossovers, etc. down the road. I would probably plan to spend $4,000 total. This should buy the necessary cables, stands, and a second power amp so I could run stereo mains and two monitor mixes
The O1V has built in parametric EQ on all inputs and outputs, compression on each channel, and decent effects (reverb, delay, chorus, etc.), but only has 12 mic inputs, 2 stereo inputs. Here's what you can do with that 1. bass drum, 2. snare, 3. over head left, 4. overhead right, 5. guitar, 6. bass, 7. keys left, 8. keys right, vocals 9, 10, 11, 12. If you need two more mic channels, you run the keys into stereo inputs 13 and 14. Ipod goes into 15 and 16. If you need more channels we're talking a lot more money.
For future upgrades the O1V has stereo outputs, and 4 aux outs. You can use the auxes to run up to four separate monitor mixes. You can also use the auxes to run sub mixes, front fills, delay stacks etc.
The O1V has the ability to delay all inputs and outputs independently. I usually delay stereo mains to the backline, and if I am running center fills and center packed subs, I normally delay them an additional 4 feet or so, so they sync up with the mains. IMHO using delay in this manner can really tighten up a mix.
It takes a lot of money, knowledge, and talent to do sound right.