Texas Trailers does have a 25,900# GN dump, at $24,000 or $26,000 with tarp kit and a few other options.
As for operating costs, do they offer permanent trailer tags up there? Also, would the trailer need insurance? From a strictly practical use, a dump truck can fit in places a dump trailer cant; but its also an expensive, one trick pony. The dump trailer should be cheaper to own, maybe more versatile, as you can drop and load, go get lunch, ect
The Texas 25DU-20; is 8070 lbs curb weight and GVW of 25,900 lbs; only leaving 8.9 T of payload. Dont know if thats "close enough" to 10T for you?
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