We were running out of room in our other two large incubators so we built this "coffin incubator". Simple to make, holds the temps and humidity perfectly. We found the foam sheets at lowes in the insulation dept. (9.99). Then bought a tube of silicone caulk (3.99). A fan from walmart (4.88). And a bottle lamp kit (4.88). We took two of the sheets of foam and taped them together to make a sturdy base, then taped the 4 walls onto the sides (used silicone to seal up all the seams), Put a top piece on with duct tape, cut a hole for a window and put in a piece of clear plastic for a viewing area. We wired up the bottle lamp and placed it at the top of the center on the back wall, then placed the fan under it to circulate the warm air. We have a large towel in the bottom to keep wet to provide humidity. And the eggs are in elevated bulb baskets. For under $25.00 we have a pretty great incubator!