I've posted about it before, but I have one that is built for hauling dekes, layout blinds and/or my layout boat. It is very long so I can wheel my boat, but it could be shorter (approx 10ft). Has a simple axle and wheelchair wheels/tires mounted on it. The thought was the more narrow the tire, the easier it cuts through mud if it sinks. Bars welded up to two handles, with crossbars and eyelets (for ratchet straps) welded in. Bottom is flat like a dolly to hold stuff in.
Works better than any cart commercially made IMO. I'm planning on making a quick change wheel setup, so I can go with fat rubber wheels on harder ground, but the wheelchair wheels work fine.
Steel is higher now, but bet you could make one for much less than the Cabelas cart...
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