It depends,..on what you get and there are a lot of other factors that come into play. Females are usually (not always the case) smaller then males. With either, it depends (again) on if it decides to hibernate or not. If it does, then that should hold you for maybe a year tops. If it doesn't hibernate you might be able to get 6 or 7 months out of it. Even that may be pushing it, if you haven't already check out the two top Gu sites the tegu and tegu talk.com They have a lot of helpful info and people over there. And quite a few babies 2 and 3 mths old that are already over 20"+.

My B&W Dino hasn't hibernated since I got him in Sept of '07 and he was over 4' when I was activated in Oct of '08. I can't wait to see how big he is and hold him again when I get home in a couple of weeks .