Holy crap! $100 for a collared lizard? Remind me to start breeding/selling them, ha!. I'm going to go out on a limb and say that it's probably b.s. that the price is so high because they deal with only one breeder, but I can only make that claim based on this knowledge:
My first collared ("texas collared" in 2001) was $60 from a really crappy local pet store in NJ, they weren't a chain so they were more expensive than usual (for everything- example, $35 for a baby iggy versus the $10-$15 you normally see them for, know what I mean?). As crappy as that place was, I got a few more there over the years, they were just the only place around that had the collareds. Every one was called a "texas collared lizard" no matter what it was. Always $60- the only exception was a really sick looking one that I tried to save ($50).
Then I moved to Florida, found Phoenix at a reptile store called Snakes in Cutler Ridge, $40. His owner sold him back to the pet store because she couldn't take care of him. It was the only time I ever saw a collared lizard sold at that store, ever. My two I have now I got at a breeder expo in Tampa for $30 each, a man in Sunrise owned a reptile place, his friend was a breeder in NM and asked if he could sell them for him at the Tampa show. Healthiest collareds I ever purchased. Only show I ever saw them at.
But anyway, yadda yadda yadda, all that aside, I think there should be a limit as far as reasonable pricing goes, and whether you deal with one breeder or not, I think $100 most likely exceeds that cap for collareds (think of it this way... who the heck is going to spend $50 for a baby iguana?)
Now, I'm really super cynical, but here's my guess:
Niche marketing: they're marketing custom saltwater aquariums ($$$) and "uncommon" reptiles to a pretty small target audience; let's face it, custom salt water aquariums typically aren't cheap, so most of the customers probably make a decent living/know more about fish than lizards. Joe Moneymaker walks in for something unique (not an igunana or a beardie) and sees these collareds priced @ $100; well they MUST be something special, they're $100! Mr. Moneymaker drops $200 on a pair and feels pretty cool, Ms. Storeowner pockets a HELL of a profit.
Or am I just cynical? I mean, it makes sense from a marketing standpoint, yes?
I don't breed, so somebody correct me if I'm wrong!!
~Tiff
"She's charging HOW MUCH for a collared?!"

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"Were the diver to think upon the jaws of the shark, he would never lay hands on the precious pearl."