I did this a few weeks back.
500lb trailer with 3,00lb of gravel in it!!
I only had to pull it 1/2 a mile like that and never took it over 20mph.
Here is a pic of the trailer with about 700lb of tools in it and the top on it from about 2 years ago.
Verses 3,000lb of gravel.
I have pulled this trailer about 4,000 miles now since getting it with no problems.
Best fuel mileage I got pulling it was 27.5mpg running 55mph with the trailer empty and no top on it.
Lowest I got was 19mpg running 75-80mph with about a 1,000 load in it.
Normally I get around 23-25mpg running 60-65mph with about a 1,000 in it.
The car pulls it with no problems.
FYI the tongue was bent like that when I got it. But hey it was free so I can't really complain.
Since I have owned it I have replaced all the lights and wiring, replaced the tires and bout a new spare, built a top for it, added anchor points in side it, and painted it.
This year I plan to replace all the wood and the bent tongue. And repaint it so it is close to the color of the car.
Oh and the car has a Drawtight hitch on it with a GSM cattback and Kartboy long hangers on the axle back section. Fits perfectly.
Only thing I would like to change is I may cut the hitch up and weld in a 2" receiver section. This would make using a bike rack easier and would give me more options for the hitch.
And yes I know "That was stupid to over load it like that".