Also, you don't know how hard it is to keep him healthy. You WILL have to take him to an exotics vet from time to time.
www.anapsid.org has all the information you need if you can dig it all out. A good book by the same author is "Iguanas for Dummies" by Melissa Kaplan. If you buy that, you'll never need to ask a question about iguanas again.
You did not say how long your iguana is from Shout-to-Vent. That would tell us roughly how old it is. Older iguanas do not have bright green coloration. But brownish colors can be caused by dehydration and stress. Your iguana right now has Relocation Stress. That can change it's color. The sooner you get him in a proper sized cage with regular water and food set out, and a nice big hiding spot, the sooner his stress will abate and he can get back to drinking, eating, and exercising.
Broken spines are often caused by physical trauma, but mostly by incomplete spike shedding. The old sheds strangle the spikes' blood supply.
The sooner you read up on him, the better.