if you're looking to upgrade, meaning you have a current TT, you should be able to get a pretty good idea of how much all the extra stuff weighs for you. i think there are too many variables to get a simple answer. DW and I only have about 400lbs of stuff, depending on how long the trip is.
important thing to consider is max payload of the truck, and consider this when you think about gear, people, tongue weight, hitch weight. i've read a lot on these forums of people hitting that max payload number before any other limit (usually)
