Desert Captain. If you read my response completely, you would see that I did not say use dry weight. No one buys a trailer, then weighs it, and says,dang, Im overweight.. or cool.. Im good. But, using dry weight, and adding 1000lbs to that weight, and taking 13 percent as an estimate to see if the truck/trailer combo is even doable works. Or, you can also take the GVW of the trailer, and then, take 13 percent or 15 percent of that, and determine tongue weight.
Having said that, with a payload of 1650, with 2 adults, 3 kids, 2 dogs, you aren't going to have much payload left for much of a trailer. I seriously doubt the trailers you're looking at will work.
Mike