Giant tegu

I don't personally own them, but one of the guys at Skiptons Pets in Boston showed me one that they had. These guys are awesome, but they get HUGE. Plus, I think it's around 400+ for one.

I've never kept one but I would like an Argentine to some day. First off you need to get the right species. Columbians can be super mean and are sometimes mistakenly sold as Argentines (the species you want). They do eat a lot so be prepared for a hefty food bill but......because they hibernate for a few months a year there is a gap where you don't have to worry about the food bill. Knowing how to hibernate them properly is important so I'd so lots of research on that before you attempt to buy one. Plus, they will need a very large enclosure when they get older, especially if you end up with a male. There are a few people on the sister site MonsterFishKeepers that have them. They might be able to help you better.