On our 25 Rear Bed model, the tank is held up by a black plastic tank cover and steel straps. I think you would have to raise the trailer somewhat to work comfortably under it. The tank itself is not terribly expensive but there are a lot of connections, quite labor intensive in a confined area.
I would make the appointment at Jackson Center, they have the parts at hand and will have you out in one day or slightly more, more than likely. Probably $1800 give or take a few hundred I'm guessing if it needs a tank replacement. They can give you an estimate.
Doug and Cheryl
2012 FC RB, Michelin 16, ProPride 1400
2016 Ram 1500 Laramie Crew Cab 4X4 Ecodiesel 3.92 axles
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