Since I have a penchant for doing costumes that are either comprised of umpteen million pieces, complicated, or I'm basically making the patterns up for (or some combination of those three), I don't usually get things done insanely fast. In terms of work time, I think my fastest to date would have been either Okita (total work time could've fit inside of a weekend, though it was spaced out -- like others have said, I can't usually spend a whole day sewing or propmaking because of other obligations) or my sleepytime Unohana. There's a lot of deceptively simple stuff out there: Miranda's dress didn't take too long to construct the basic shape of, but the inset white took far longer than I expected, and the corset and petticoat for the period silhouette had to be done as well.
Guess that's a tl;dr way of saying that while I can breeze through an easier cosplay in a weekend, most of what I do is just crazy enough to take me probably at minimum a solid week's worth of crafting time. (And then there's the truly insane ones: I've already spent several hours just doing the handsewing on my Trinity Blood costume, and that's for the bias tape on the veil alone.)
