I suppose it depends on what you usually haul. Pickup bed trailers have a high floor that make it a pita to lift heavy stuff or load something that rolls. The wheel wells really limit what you can haul, and tying stuff in/on is another pita. At least with the topper on it, whatever you can get inside should stay dry in a rain storm.

That price range should put you at least 3/4 of the way towards a new real 4' x 8' trailer that you can actually haul stuff on. I bought a new Harbor Freight 4' x 8' trailer on sale for $266, then added treated a 3/4 plywood floor, added a 2" ball coupler, some locks for the bed folding point, and with title transfer & plates was ready to roll for around $450. It folds up and stands on end when not in use, and has a tilting bed. Much more useful the truck box trailer, and I've had and built some of those. Gene