I can't speak to what toads can or cannot be towed on a dolly but I've been very happy with my Demco Karkaddy SS dolly for the past 11 years. It's fully galvanized so you never have to worry about rust, has surge brakes so any vehicle can pull it safely without having to install a brake controller, its ramps fold up and the tongue folds back to reduce home storage by almost 50%, it has rack & pinion swivel system rather than swiveling wheel plate and Demco is very receptive to answering questions if needed. It may cost a little more but I've felt it was worth it.
Dave