Like previous posters said, if you have the cage space for a bearded dragon then your best bets would be uro, blue tongue, or ackie. Uro and blue tongues are probably less expensive than ackies, but don't rule out the little monitor. These are so far my favorite lizard species, and mine is always very happy to be handled.
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0.1 ball python
0.1 corn snake
0.1 rosy boa
1.0 bearded dragon
1.0 leopard gecko
0.0.1 yellow ackie
1.0 greater earless lizard

0.1 quaker parrot
1.0 fischers lovebird