What are you currently keeping? Sandies in my own limited experience seem to be fairly simple to keep happy provided their basic needs are met (space, hides, digging substrate, a decent hot spot and loads of patience and personal space for the animal). That being said, they're quite the commitment. They start out small and adorable but will grow up to and over a metre long, five of their six ends are death (with the sixth capable of giving a painful tail whip) and some individuals can have a pretty crazy feeding response. Yesterday one of mine decided my phone was possibly food and rocketed out of his enclosure while I was attempting to take a photo of him! He mostly bit my phone. Mostly.
They also are not like bearded dragons, interaction with them takes a lot of patience and building of trust between the both of you. All monitors will tell you where to go if they feel threatened or are not in the mood.
I'd really recommend a book by Dr Danny Brown, called "A Guide to Australian Monitors in Captivity". It's invaluable, and has loads of info on most locally-available species, including common medical conditions etc.
Also check this
thread and
this one. Loads of good stuff on interaction here, and also some good discussion about beginner species, should help to give you an idea on what you are in for.
They're really quite rewarding to keep but need patience and room.