A novice should not, under any circumstances buy a chameleon less than 4 months old. The chances of its survival in the hands of a novice are very slim. Chameleons are VERY expensive to keep. Between the caging, the live food, the vet care, the UVB lighting, etc., the purchase price is a small part of the cost and the very last place to try to save a few bucks. Buy from a reputable dealer such as www.calumma.com. There are others nearer to you but their names escape me. And whatever you do, do a ton of reading and get everything set up before you get the cham. Read the husbandry articles at www.chameleonjournals.com and the calyptratus profile at www.adcham.com.
And in case you were under the illusion that veileds are "desert" chameleons, they are NOT. They have the same difficult hydration needs as most other chams.
Ed