when you check Craiglist for coops, be sure to search also for Shed, Playhouse, and Kennel ... also Cage
several interesting items on the Olympia area Craigslist now ...
sometimes there are cabinets, dressers, hutches, breakfronts .. that can be repurposed as at least grow-out coops
edited to add: entertainment centers -- your nest boxes are virtually already built ...
some of the listings of crates, would be sufficient for a small flock, especially the larger shipping crates (no, not necessarily the great big crates that Broodytood and I got; but many places that sell equipment or motors of various sorts, get crates that are well built and bigger than a breadbox ...
occasionally there will be someone offering "scrap wood", or pallets, and I've seen awesome coops made out of pallets
power tools are not necessarily required -- a good crowbar might be ... and a hammer and screwdriver .. I also found a large stapler came in handy, for attaching fence-wire or hardware cloth
of course personally I would not like to live without my trusty Makita ... cordless drill/screwdriver ... and those show up secondhand at reasonable prices since many people buy the newer smaller lighter devices ... for coop building you don't need Tim-Allen's-More-Power tools !!