A bunch of questions....

I have some questions that I haven't found the answers to in books and caresheets.

Can monitors be potty trained?

What species of monitors would be best suited to a free roaming type of living arrangement?

What species of monitors tend to be "friendlier", or more human oriented/tolerant?

My 17 year old iguana passed away last February, and I really miss having a giant lizard friend around. He was very social and crawled into people's laps soliciting head rubs and such. Rather than rush out and adopt another iguana, I wanted to investigate the other giant guys out there and see if there are any monitors/tegus that might be a good match. One thing I really liked about the iguana was the fact that he never needed a cage. He just had a few basking spots and the rest of the house was fair game. I guess I feel like I don't want to have a huge lizard that has to be locked in a box most of the time.

Our home is in Tucson AZ, so we are hoping to build a nice outdoor recreation area for whatever companion we bring home.

Sizewise, I am also looking at something medium. A water or nile monitor would probably be too large. 30 lbs max or about the size of a large male iguana. Some people have suggested black throats, peach throats, or argus (I love argus monitors! they are so beautiful!) I am having problems finding husbandry info on these species though.

Anyway, please if anybody has some suggestions of where to look for info, suggestions from their own experience, etc. I would really appreciate it. Thanks for your time.