I really like the quad trailer Zieman makes. It has a locking storage box on the front, along with a rack for gas cans and a bar to secure them.
Mainly, I like the way the 4 ramps slide out from under the deck, and that it is very secure and stable on the highway.
Downside, I suppose, is that if you are in the rust belt it is steel... and also I don't think it is too light.
Anyhow, watch the classifieds and I'm sure you will come up with something decent that meets your needs.