I love creepy-crawlies. Snakes, lizards, all that. I know it's off topic, but...
I thought goannas were usually fairly smallish, maybe 1m? Komodo dragons (the largest living lizard species at 2.5-3m) are nothing but a huge monitor lizard. I think the ones in the documentary were around 1.5-2 m. I'd think if you could handle a Great Dane in an apartment a monitor wouldn't be such a problem, especially since lizards don't tend to be very active. Mostly they seem pretty docile; they're kinda fun to play with although they do carry salmonella on their skin. But the image of them eating their owner is pretty powerful. And gross.
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