Just do not buy your Leo from a pet shop. I hear they put a high price on those there. Leos are just about the easiest reptile that I have ever taken care of.
You can make a hide box out of a ziploc plastic container and some course sphagnum mulch purchase from home depot. Substrate can be newspapers (free or cheap) or sand can be purchased at home depot. All u need is a water dish and a food dish (if you want cheap cut the bottoms out of plastic cups. That is what I use. Calcium supplement purchase at a pet shop or reptile show. Use a milkcap as a supplement dish. Use a stick in the yard for them to climb on. If you are anal about parasite stick it in the oven for a few minutes at 350 and watch it. I'd soak it first so it does not combust on you. I did not do that by the way (the oven trick) I was lazy.
recap on pricing...
Leopard $10-20 if bought from a dealer or at a reptile show
Substrate
$3 for a bag of play sand
Free or cheap if use Newspaper
Hide Box/Humidity chamber
$3 for ziploc containers
or
Go to dollar store and buy cheap plastic container
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14 Leopard Gackos 5.9.0
1 Baby Leo (Joi) 0.1.0 temp sexed (Found a new home L.F.)
2 Tokay Geckos 2.0.0
1 Graybanded Kingsnake 1.0.0 (on vacation in my house)
1 Baird's Rat Snake (Thanks Vadoni!) 1.0.0
1 Trans Pecos Rat Snake 0.0.1 (currently has eye infection)