We saved some money before quitting. We're staying with friends (paying rent) to save costs on housing. But we live in SF, so it's still pretty expensive. In the Mission, you can get tacos for cheap, and, hey, they're pretty good. :)
For marketing – not much. Relying on blogs, forums, word of mouth, featured promotions in the App Store and in Android Market (and in Windows Phone 7). We bought a few ads, but they weren't super effective. Focusing on marketing is something we will do for our next game, but since we're strapped for cash it's hard to compete with the social farming gaming behemoths in terms of climbing the ranks through advertising.
Also, what avenues of marketing are you using?