Wow, what a trailer.  All I can say is I bet that is one hard pullin' SOB if you get into a little headwind or hills.       If you have a need for that big of trailer then that is great, generally when horsetrailers get that big it is time to pull out the Semi .      Pickups with them kind of loads usually cannot get more than about 6-7 miles/gal especially with winter deisel pulling them loads.  Therefore your not saving much over a semi, also trucks have less tire issues,  I've never had much luck with triple axle trailers.              With  that being said the demand for a trailer that large may hinder the value some,   I would say it is worth all of 6-8,000, considering the price of aluminum it would scrap for about 2K probably.        Good luck