Tongue Weight on 2619

I am interested in buying a used TrailManor 2619. After looking at the manufacturers specifications it appeared to be a good match for my 2002 Silverado K1500. I weighed my truck and found out that I had a little of 1100 pounds of weight carrying capacity. The dealer checked the tongue weight on the TrailManor and it weighed 700 pounds. I was surprised because the TrailManor brochure stated 351 pounds. However when you consider the weight of water, two batteries, and two propane tanks all in front of the axle it does seem to calculate out. This weight would put me a couple of hundred pounds over my GVWR, and I still have not taken into account the weight of the camping supplies that would be in the trailer. Has anyone checked their actual tongue weight? Does this tongue weight seem right? I would appreciate hearing from current owners.