Quick question following a long story...

I just recently moved to southern Arizona and am looking to get a Sulcata again. Growing up I had a red foot and baby sulcata that I housed for a local zoo during their restoration and miss the experiences and thinking of getting another Baby sulcata again. I'll be in an apartment for the next year but have enough room for a large indoor pen. I have relatives that live further out in the desert and are allowing me to build a small pen and from time to time I want to take him there and let him walk around for the day. I want to know if any one recommends it? The pen will be enclosed so I don't have to worry about an animal getting him and plus I'd be outside at the same time. Just wasn't sure if health wise would it be a good idea. Any help would be appreciated. By the why, how much do these little guys go for now a days. Looking for something small, no more that 5-6 inches long. Maybe less. Thanks