I think Iguana's would be a great idea if you could get your hands on them. I kept a red and a "blue" iguana together for a while. They interact and unlike most monitors they don't get all crazy on you when you take them outside. I'm assuming you haven't kept many reptiles in the past? If so, an Iguana can make a great beginner pet. You can buy their food at a grocery store. However, they aren't easy to care for despite how common they are. It'd be a challenge, but in the end it would totally be worth it.
My male has still most of its juvenile coloration but that will change. I gess he will be very colorfull when he matures
) ,clean the mess they made, prepare food,etc. Vet trips can be expensive.lol