There is not a lot of options in a hard sided trailer at 3,500 lbs max towing weight.
You WILL be looking at some very small trailers, most likely not more than a bed.
One of the ones that comes to mind is the Tab trailers, looks like the old "tear drop" trailers of yesteryear with today's prices :E they don't come cheap.
CLICKY LINK TO TABAnother option could be a Aliner but I am not sure if they are still making them. Aliners are a cross between a popup and a hard sided trailer. Basically it has hard sides that fold up and down so you will have some setup and tear down work to do.
I personally would not use a vehicle rated that low to tow much more than a Skidoo or such since those vehicles tend to be not really designed for towing..