I actually don't prefer fixed-bid projects and I wouldn't attempt to do such a large one in such a short amount of time. But I live in Boston which has a nice startup scene and people approach me to build web applications for their startups.

I've been meaning to build a go-to website for about half a year now, but I've been too busy with client work--they find me without the website, often through the Boston Ruby Group.

If a solid month of work for $25k seems like "a big project" then maybe you're not billing enough.

If you're making $25k * 12 = $300k just by working you probably have some kind of specialized skill. If everyone could do it, the price wouldn't be so high.