We do runs around construction sites, usually bigger building projects, and dumpster dive. It’s better to ask the site foreman for permission, but they usually tell us that if it’s in the dumpster we are welcome to it. Also , Lowe’s and HD will put scrap pallets and damaged lumber behind the building , if you can get to it before they haul it off.
Someone nearby used trellis instead of wire on their coop, until they could afford to buy wire.
Lowe's will give free pallets...I got a couple from them before. Just ask them if they have some old pallets to give for free... You are doing great!!!