How big are tongo lizards?

There's no such thing as a "tongo lizard." It's likely you're thinking of a Tokay Gecko, which is a type of lizard native to Southeast Asia.

Tokay geckos can grow to be quite large, reaching up to 12 inches (30 cm) in length. This includes their tail, which can be about half their total length.

If you're interested in learning more about Tokay geckos, I recommend searching for information about them online. There are many resources available that can provide you with more detailed information about their appearance, behavior, and care.