>>That is possible, but there are a lot of variables. The talent and skill of the builder. Also the ability to make the cage water tight. Without risking the health of your snakes with chemicals. I have done both and if you can find used cages that are in good shape you would be ahead of the game. Your also have to factor in your time. Materials are just a part of the total cost of a cage.
You don't need much skill to make a basic cage which is just a wood box with a hinged piece of plexiglass for a door. There are several paints and sealers you can use that aren't harmful to reptiles, such as Drylok latex masonry sealer, water-based polyurethane, or high gloss latex bathroom paint. As for time, you can get the store to cut the wood and plexiglass for maybe $10, which leaves about an hour to assemble the cage and another hour or so to apply paint or sealer. I'd rather spend $100 and 2 hours on a cage than $200-$300 or more. If you need several cages, you can spend a Saturday making 5 cages and save $500-$1,000. I'd consider that well worth my time. And most used cages I've seen weren't very cheap.
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MY COLLECTION:
1.0 '04 Columbian BCI
0.1 '05 Blood Python
1.2 Ball Pythons
MY WISHLIST (I turn 18 on June 16th
):
A Northern Blue-Tongue Skink
1.1 Brazilian Rainbow Boas
1.1 Hogg Island Boas
1.0 Salmon BCI
0.2 Columbian BCI
1.1 Sumatran Short-Tail Pythons
1.1 Borneo Short-Tail Pythons
1.1 Dumerils Boas
1.1 Suriname BCC
1.2 Spotted Pythons
2.4 African House Snakes
1.2 Rubber Boas
2.4 Bearded Dragons
1.2 Rankins Dragons
2.6 Crested Geckos
1.1 purebred Dobermans
0.1 black German Shepherd
2 ferrets
A Senegal Parrot
A Sun Conure