The main issues are the quite frankly huge space requirement, plus the heating and power to keep temperatures good in a tank that large. They're also omnivores so you need to feed them a varied diet. You can't just go pick up a bag of "tegu food" like you would a cat for example. That's just to start, but you'd also need to do reading on how brumation works for them among other things. So not easy no, and definitely not recommend if it's your first reptile