Leopard Geckos are very easy to look after and to handle. Just be careful that a youngster doesn't grab their tail roughly, as they can drop them.
Watch out - a lot of caresheets say that you don't need UV lighting for leos, but this isn't correct - they are very efficient at using even small amounts of this - which helps them produce vitamin D3 and aids calcium uptake. Their food should be dusted with a balanced calcium / vitamin supplement as well.
I've never kept cresties, but they can be a bit flighty and quite delicate. Not necessarily great for youngsters to handle, but they tend to be very tame.
If you have a bit more room, bearded dragons are great as a first time lizard. You might also want to look at water dragons. There are several types of these, but they all have pretty good temperaments. Also, have a think about mountain horned agamas (or mountain horned dragons, as they are sometimes known.
If you want something a bit livelier, check out Ackie Monitors. These are fantastic to watch hunting and are usually pretty easy to tame. They are lightning fast, though!
There is a huge choice, to be honest!
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