Yes phantom power is something you want for sure!
If you tried to plug in a condenser and you didn't have phantom power you would need a pre amp or another power supply for the mic its self!

What recording programs are you using?

You're asking a lot for not a lot of money. Limiting yourself to USB means that likely, you will only be able to record two simultaneous channels at a time. The fact that you want it to be powered is something else altogether. I don't think there is a powered mixer out there with USB capability.

I think you're going to have to reconsider your budget. Get your bandmates to fork over a bit more.

Carvin offers a couple of powered mixers with USB. But, like Hueseph pointed out, USB is only 2 tracks-very limiting. You probably should look at a FIREWIRE mixer, and the Mackie Onyx line is great for this (they offer an optional FW card for their models). Save up a bit more for one of these and you'll be glad that you did that down the road. A FW-equpped mixer will typically let you track up to ( 8 ) seperate channels,each to their own track. This is a definite plus. In addition, the Mackie gear tends to be a better build quality compared to a lot of their competition.
BTW, I understand that you want to do "double duty" for live gigs, that's great. Try to stay away from a powered mixer, though, because their inherent noise will not help your recording quality. Learn to use a seperate power amp.

Well here are a bunch of USB mixers:
http://www.dv247.com/search/3772/0/ProductPrice/Ascending/-/1/

I think ether the Alesis MULTIMIX 16 or ether of the Allen & Heath ZED might be what you are looking for?

I have no idea how these things perform tho, sorry.

I would avoid the multimix at most every cost if you intend it as an interface. In fact I would avoid USB for a recording interface period-especially when the track count exceeds 2.

The ZED-R16 is another matter entirely. I'd also second the idea of a serious look at the Onyx mixers w/firewire card option.

TheJackAttack wrote: The ZED-R16 is another matter entirely.

What do you mean by that?

I like what I've researched on the ZED R16 regarding the fw portion. Apparently it is more flexible than the Mackie Onyx and individual channels can be returned (and hence summed) through the ZED. I've only used large format A&H boards so I can't really comment on the small format stuff specifically other than reading.

The Multimix gear. I have had on numerous occasions with more than a few persons assist in getting it more or less functional as a an interface because the drivers are not good. User forums aren't necessarily a good indication of quality as mostly only people with problems post with vehemence but the sheer preponderance of driver issues-not just with Vista-is overwhelming (or underwhelming depending on view).

The Onyx series I own several flavors of (1640 and 800r) and like the sound of the pres and the converters are good. What I don't like about the Onyx fw mixers is that I can only return a stereo feed to the board-no summing in the board. I understand why Greg Mackie designed it that way. User simplicity. And most of his target market was small bands that may or may not want to make recordings. And he was really wanting to market the 400f and 1200f as the choice computer interfaces and not mixers.

Another option in this range is the Yamaha 01V96 which seems to get good press here at RO. I friend of mine in Billings has the LS9-16 and likes it but I haven't done more than look at the manual for either of these.

TheJackAttack wrote:
The ZED-R16 is another matter entirely.

You might want to give out the manufactures name too

A&H = Allen & Heath

There seems to be a bit of wrong info here....

USB 2.0 can certainly handle more than 2 channels of audio at a time. (Perhaps you were thinking about the original USB spec?) USB 2.0 is almost indentical to the Firewire 400 spec in terms of bandwidth and speed. (Don't recall the exact difference, it's not important enough to make a difference, really.)

In most cases, however, things have evoled to the following general rule of thumb:

Firewire for audio interfaces, capture cards, audio mixers, control surfaces, HDV cameras, etc.

USB 2.0 for storage and peripherals: External HDs, mic, dongles, memory sticks, etc.

These are not unbreakable rules; there are manufacturers that have both features on their gear, but you get the idea.

For my $, it's the Mackie ONYX series, with a variety of choices & models for what ever you need to do in a case like you describe. There are always some limitations, of course, and other manufacturers have jumped in with some pretty good stuff as well.

You're right of course Joe. The problem with USB 2 for audio is more the fact that it is a "dumb" interface and does not reliably transfer large amounts of data without glitches. The new USB 3 that is due out sometime in 2010 should rectify many of my issues with USB as an audio bus.

As it stands right now my experiences mirror your guidelines.