We have pulled a 28' stacker trailer weighing about 14,000lbs a few times the last 3 years. Used for hauling additional race cars and equipment to Florida for SpeedWeeks with our 03 Tradition.
If you look at all aluminum stacker trailers, three of the best are Featherlite's, ATC or my favorite, GoldRush. The weight of the trailers have been around 4500 to 5000lbs plus whatever you are hauling. They are not cheap, but the tow fantastic and they hold their re-sale value well.
One way to keep the weight down on the trailer is to skip the steel internal lifts some manufactures use. I would go with the automatic lift gates (your rear trailer door) and haul the bikes and golf carts in the overhead and your vehicle down below.
We beefed up the hitch area, make sure we are using the weight distributing equipment and have not had any issues. When properly loaded, almost did not know that trailer was back there fully loaded except for the 1mpg drop in fuel milage.