It takes me 30 hours or so spread out over at least a week just to do the outside when I am doing it as a job; I already have all the tools, trays, supplies, and colors I need.  It takes me a month or more of scratch time when I'm doing it for fun, and then only if it's in the middle of things so I can sit down while I am making coffee and the onions are caramelizing; or can paint and sand while I watch a movie and productively use all the little snatches of time that can fill up a day.

;^)