We feed only crickets, our adult eats 3 "large" every 3 days, around here at an independent store that is $.08 a cricket. (and a 30 min drive each way, but she cares about her stuff.)
When they are younger, you run into the problem that they are growing and need extra food, but might not be able to move to a bigger size cricket. (I'm sure something like this happens in snakes.) So for your first 9 months on average you will have periods where you might be feeding 8 or 9 crickets daily because they are just between those cricket sizes. A few more weeks and then you are back down to say 4 of the next size up daily.
Don't forget to factor in cricket food and vitamin powder, but I think we spend around $10-$15 yearly for all of that, but if that makes a difference.
Personally, once they get to adults, save for the electricity, they are very cheap pets and too much fun. Hope this helps.
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0.1 Albino Leo Gecko
0.1 Crested Gecko
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