Hello rayandre -- welcome to the forums!
This link is Jackson Center's FAQ's list of weights. Hitch weights can easily be 200 pounds more when ready to go camping. Lengths can be up to 11" more than the length listed for the model; eg, my 25-footer is actually 25' 11". Many don't add quite that much. Widths -- pre-1994 figure 8' wide; my '74 Argosy is more like 7' 10". Argosy Minuets are about 7' wide. The smallest of the small Airstreams (60s Bambi or Caravel) are... help me out here folks.