http://www.trailmanorowners.com/foru...left+open+adco
We also bought the ADCO cover; we have to secure it to the trailer hitch in the front and also to the rear (we have a spare tire mounted on the rear bumper) to keep it from flapping around in the wind.
If you do buy one, be sure to wrap something around the sharp edges (bumper, corners, etc.) so that the cover doesn't tear. I have been using leftover styrofoam pieces that come in boxes with TV's, electronics, etc. and taping them to the corners.
We're very happy with our ADCO cover. I read somewhere that you should buy one 2' longer than your actual trailer length (maybe on the ADCO box?).