Don't think I said anything about this, but if you want to flatten "little" things like desks and file cabinets, build your own version of a Car Smasher.
Buy an old Cardboard Baler machine - cheap and easy. Place the file cabinet or desk inside and hit the button, and it'll turn into a Latke. I do NOT suggest sour cream or applesauce...
Or make your own and scale it way up, a couple chunks of 1" thick plate for the mashing surfaces, and a pair of large-bore hydraulic cylinders one at each end. A hoop of I-Beams between the two halves.
It can go straight up and down, or you can make it hinged - two hinged leaves to meet in the middle and it can swallow a whole car at once. Just remove the non-compressible items like the engine block and transmission first.
And strip aluminum stuff like the radiator and AC cores, it's worth more as clean aluminum.
Oh, and pull the battery and brake/clutch master cylinders too, or it gets messy handling the pancake with sulphuric acid and DOT-3 (paint stripper) dripping all over.
If you give a little pump a few minutes to cycle, it can do a lot of smashing.
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