I'm also an iguana expert, so to speak, that within the past year aquired leopard geckos. Here's what I know thus far:
They can live 20-30 years. You should feed them as much as they'll eat at least 5 times a week. Leopard geckos are great for handling, especially for kids, that's why I got mine mostly. They are very docile. With iguanas, you have to worry about being scratched, leos don't do that. They also don't need the uva/uvb rays like iguanas, and an undertank heater is sufficient. A 10 gallon - 20 gallon tank is all they really need. They are also really easy to care for in general. Way easier than an iguana.
The only advice I can give to you is to stay away from sand as a substrate. They can become impacted, and it's not pretty. For substrate, I use either that brown paper that comes on a roll, or ESU's reptile carpet. A lot of people use tiles, which I think looks really nice.
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~*Chibi*~
Sir Iggy ( 1.0.0 El Salvador Blue Iguana), Ryo-ohki, Orion, Bud, & Finnegan (3.1.0 crazy kitties), Rosebud (0.1.0 cockerspaniel), and Kayko (0.0.1 leopard gecko)
