My 2 cents (plus a little):
1.
As I read this thread I remembered that a local door store (The Door Store if you're in the Puget Sound area) always has a pile of old doors in front & anyone who wants them can take them.
2.
If you go to pawn shops, have a good idea of the retail price of tools. The pawn shops in our area charge ridiculously close to - or even over - retail. You can negotiate price in pawn shops. Vote with your feet if the price is too high and they won't budge.
3.
When I got our chicks, I intended to get an old dog house off craigslist & convert it. DBF vetoed me and would up spending $200-ish on materials for the coop. Granted, it's going to be a fantastic coop but everything that "fantastic" about it is for us: height, accessibility, storage, etc.
4.
A critter that will sit in its own poo doesn't give a lick about aesthetics. If you construct a "starter coop" that protects them from the elements & predators, that's all that matters.