I personally Haven't seen many cuddly geckos or dragons either though, so I don't see why people would recommend them when some one asks about taming chameleons. You don't tame wild animals but you make them more tolerable to you and their surroundings. As an owner of reptiles , Not being a threat is probably your biggest key into gaining the trust of your animal. Routinely cleaning feeding and other non handling activities should be enough over time to let your chameleon know your not a threat. Having them young with proper care they should tolerate you but as any species some are just pricks and dont like people or other things and will show you. Like cameras, vaccums ,showers ect. You will get to know your chameleon and you should know what it likes or dont like over time.
There is plenty of cost for good training. It's expensive too.. Im talking food and proper setup... not on practicing to jump through hoops : )