DIY Snake Enclosures Heating

[Corwin]

Hello,

I am building some snake enclosures out of 1/2" MDF/Particle Board (painted on the inside to seal them, and siliconed on the corners). I was wondering how to heat them without spending a lot of additional money (we are already spending 40-50$ per enclosure). We have used Heat Lamps Solely in the past, though i understand those are not sufficient.

A bit more detail on the cages, they will be 26Dx25Hx31L (outer dimensions), mostly out of 1/2" MDF, the back top 6 inches will be peg board (for ventilation). the opening/doors to the cage will be wooden framed glass on hinges). They will be 2 inches from the wall (again for ventilation of the pegboard). We are build at least 6 of these enclosures, potentially 8. they will stack in stacks of 3.

What would be the best way to heat through the 1/2" MDF while staying on the cheap side of things? I see Heat tape recommended alot, however it seems very expensive as one needs a thermostat, also would it actually be able to heat through the wood? in addition it seems very complicated to set-up/install. There are also those heat-pads, but those seem pricey too).

Would heat Lamps work for this (if i were to use a heat lamp, i would make a an gap in the top of the cage, lined with wood on the sides, and fiberglass mesh on the bottom (to allow the heat through).

I received some feedback from someone, and though of this based on that:
if i cut a hole in the bottom of the cage, say 11x11, then i place a 12x12 tile (ceramic or thin wood) over that and silicone it into place, would that be an effective way to have heat tape heat the cage?

Also, where can i find cheap thermostats, best i have found was 50 unwired, 79 wired. . . ouch.

Thanks!