Does the 550-600# passenger weight include the driver's weight?
How much additional cargo would you expect to carry in/on the TV?
Do you plan to use the same TV and TT for a few years?
If so, how much weight gain do you expect from the passengers while you are using this TV and/or TT?
Would you expect to be using an extra-heavy WDH such as Hensley Arrow or ProPride?
Even if you can limit the total weight of occupants and cargo to 700# and then add 80-200# for a WDH, you'll have only about 1400 minus 780 to 900 = about 500-600# for the remaining amount of trailer-induced load which can be carried by the TV.
Assuming the WDH is adjusted to transfer a load equal to 20% of tongue weight to the TT's axles, and a tongue weight equal to about 12.5% of total loaded weight, the TT's maximum allowable loaded weight would be about 5000-6000#.
For a family of your size, it would be prudent to assume you'll need to add about 1500# to a TT's factory-delivered empty weight.
IMO, you should be looking for TT's with a sticker empty weight of 3500-4500#.
Probably not many in that weight range which could sleep up to eight.
Ron
