Argentine Black and White Tegu's are very interesting display animals, provided that you have the space. They exceed 4.5', so make sure you have the space, but are very docile animals with curious personalities. When young they reportedly are a little flighty and nippy, but it quickly passes. If you go to agamainternational's website they have some good information about them.
Savannah Monitors are also good lizards for displays. They normally are very docile and around 3-4 ft long. Once again, make sure to handle them while they are small.
Water dragons (as stated before) may also be good display subjects, but unfortunately I don't know a whole lot about them other than the Austrailian variety may be more docile and colorful than the Chinese species. Again, Agamainternational has useful information on Austrailian Water Dragons.
Good luck
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Sean M
Currently have:
0.1 Antherystic Elaphe Guttata Guttata - Corn Snake
1.0 Elaphe Vulpina Gloydi - Eastern Fox Snake
0.1 Leucistic Elaphe Obsoleta Linheimeri - Texas Ratsnake
1.1 Morelia Spilota Cheyni - Jungle Carpet Python
Saving for:
Agkistrodon Contortix Mokasen - Northern Copperhead
Varanus Exanthematicus - Savannah Monitor