Australia has many different varieties of monitor lizards (in Australia monitor lizards are referred to as goannas). There are many different varieties, pygmy varieties grow no larger than a human hand right up to the large Perentie monitor that can grow up to a length of over 2.5 m.
We’ve not heard of anyone keeping goannas as pets in Australia, and at this stage have little we can report about them. Overseas, water and Nile monitors are kept as pets. Some people keep them in large enclosures, others let them roam their houses though having watched some videos on Youtube today, I would not be doing this personally if you had other pets, or young children!
Are you a Herp Expert in Australia and able to fill in some of the blanks for us about keeping goannas as pets? I’d love to hear from you firstname.lastname@example.org