How to build a lizard terrarium
Look for large aquariums on Facebook marketplace and / or Craig's lit. Maybe less expensive to convert an aquarium rather than built one.
Once you've got that aquarium, make a heavy screen top for it from 1/4" hardware cloth. Then depending on the type of lizard you have, recreate their natural environment.
Get pieces of fiberglass or Lexan cut to the size you need for the front and back, and for the sides. Depending on the size of your lizard 1/4” thick for a large lizard, 1/8” thick for a smaller one. Glue on outside corner molding, found in home improvement centers, to attach the sides and corners. Super Glue would work well for this. Get a piece of 1/2” plywood cut to size so it fits inside the unit for t
(my response got cut off)...the bottom. You can glue it in if the plywood is nice and tight. If not you can drill small holes through the sides and install small screws to hold the bottom in. To finish it off put another piece of plexiglass to cover the bottom. This will protect the plywood when the lizard urinates.