Before purchasing a leo you will have to think about the supplies it needs to survive.  Here is a list of the supplies it need:

Normal Leopard Gecko: $20- $60 ( you can buy it at Pet-co for $20 usually )

All glass Aquarium  10 - 20 gallon $7-$27

Screen Cage Lid ( not needed but recommended ) $7-$20

Lighting  Dome  $9-$15 ( or old lamp )

Under tank heater   $15-$30( depending on tank size )

Hide Area  $5-10 or ** free** if you use your imagination

Water Dish/Calcium Dish $1-$7 or a large cap

Substrate  $9-$20 or newspaper/paper towel will work the best

Cricket/Mealworm  $10-28/month

Miscellaneous $0+ ( like background, drift wood, rocks, etc... )

It average to about $100. Are you willing to pay that much for a Leopard Gecko? Also are you willing to spend 20min. of your day to feed it and observe it? If you can't,  it better off not to purchase one then to purchase one and just let it die. But if you can live up to these commitments then here is a good site where you can find your supplies:

 

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