I got several cage I bought, personally made. I would help you by posting pics but I don't got a cam so I hope you'll accept ideas. If you really want your monitors to be comfortable, there is a two sections cage that I have. On one side I got all the ceramic/uv/heating equipments. Since it is a tree species I put many climbing branch. Deminsions 5'x4'x4'. Heater all the way above and out of reach. So if he wanna bask there is a branch exactly 6 to 7 inch moving slowly up. On the right side 2 feet near the bottom there is a hole opening to the right portion of the cage. There is his resting place, always kept dark and warm. It is a round tree bark that he rest in, makes it seem like a hole in the tree. It can break off in half if I need to clean it. Left side is for the heat/light/food. Right side is for sleeping and hiding.
Other designs are built for larger ground monitors, which dimensions should be largers on horizontal than vertical as they don't climb as much as the smaller lighters species/babies. There is a hole near the corner on the right side, above the hole it has a cover so nothing goes into it other than the lizard. Its kind of like a burrow. Open ventilation left side and inside his burrow. Only clean his burrow when he is out of it, they don't like being disturbed so. Sliding glass doors and wood frames make this cage very accessable when needed. Only thing is $$$$$$$$$.