With 13 riders in the family, I bought a trailer that would handle bikes from smallest to largest. 3500 pound capacity, 15" wheels set up with 3 wheel chocks to tow 1 bike in center or 2 bikes, 1 pn each side. Of course I tow it with a Honda pickup, not a passenger car. I used to have an enclosed trailer, but I hated the weight and not being able to see thru it when towing. It did protect the bikes much better from the elements or prying eyes. This one I can move to the vehicle rather than having to back the vehicle up to it. Unfortunately it is forced to sit outside all year.
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