My neighbor is a pure bred scavenger, and his favo quote is: " youve either gotta keep your eyes open, or keep your wallet open"

He's very right.
I bought a self loading 3pt hitch feed dosing bunker, for 250 euro last year. I also bought a flail shredder for straw, with the intention to join both into a big bale shredder for our 30 horses (of which 15 of people that rent a stable at our place )
Right now i have different plans, i also wanted to build a bush hog (in Holland there arent any second hand ones available, only light duty pasture toppers but no brush cutters) but i decided to replace the straight blades of the swath chopper/spreader for the optional heavier cupped blades, so i can use it as a brush mulcher. The feed bunk i put on the internet again, because i dont have enough time either.
On this dosing bunk, with a self loading comb, conveyor and loosenign drum, there are 2 hydraulic motors, 2 very nice cylinders and a few meters of fairly new hydraulic hose. If i had to buy those hoses new i'd be spending at least 400 Euro. Then there is the spool valve block, sprockets and chains, a few meters of usefull tube steel and there is a couple of 100 kg of scrap steel, which is worth about 14 cents per kilo right now.
When i bring a car to the wreckyard, the rear axle and complete front end with transaxle is saved for later, there is allways a use for a good axle with a commony available tire and rim size.
When i put old wagons to the scrap, i cut off as many tube and profiles as i can, they allways come in handy.
When you keep your eyes open for bargains, you can save a lot of money against buying new, or buying at the wrong time, because then you'v got to pull your wallet open.
And IF you have to buy new, have a look around. The average farm dealer sells steel for 3 Euro per kilo, where i buy it from my boss (in exchange for a couple of unofficial saturday working hours) for wholesale purchase price, which is about 1 euro per kilo.
The heavier the beam, the more effort i take to save a small length from a cart of scrap i sell. I just take my time to cut out the usefull pieces and sell the rest for scrap even though i cant wait to start on the next project when i am cleaning up my workshop inbetween projects.
with a bit of creative thinking, you can also use components of old machinery in your new stuff.
Or build a subsoiler, you can use pieces of heavy truck leaf springs as chisels, spring steel matches the wear resistance of manganese steel, though manganese or borium or hardox, is lots more expensive than mild steel, especially if you buy at a local hardware store.