Why would it have to be in a real office, anyway? You could use the greatest resource we have - Hard Light.
The only real difficulty with this idea is focusing it all. Although if you got about twelve of the community's brightest stars, and they were dedicated enough to do something every week, you'd be well off. Modelers do one model every week, mission designers, one mission, coders, one good chunk of code.
Money-wise, well, since most of the dev members would be doing something else to get bye in the real world, you wouldn't have to pay them until you've got either a product or some good collateral.
You'd be pretty much set.