First, there is no verdict. Which is a good thing from what you said. The verdict comes at the end of the monitors life. (the quality of life)
Your simply going for a start, a base to learn from. Two things, the lite should be in the cage. Then you can use less heat and create a greater temperature range with the benefit of less dehydration. And you do need some ventilation. Some perfer ventilation on the sides, some on the top, me, I could care less, in fact i perfer it to be my poor craftsmenship, hahahahahaha.
Dirt from your yard, could be horrible(very high percentage of that), if your pretenting to do research, then your first step should have been to read all about the species you intent to work with. There are little bits here and there in hundreds of books. But, you will find that ackies are bound to certain types of soils. Types of soil found in the desert, you know, poor draining arid land soils. The kind many cactus need. Even there they live in pockets that have two main elements, sun exposure and soil type. Even species/types of ackies that live in areas that are not considered desert, in the top end and the kimberlys, monsoonal areas, they to, only occur in areas of draining soil. So if your yard has nice rich soil thats great for growing grass and flowers, then that is the wrong stuff.
Also consider, the deep dirt everyone is recomending is mainly for nesting, your hatchling will not be nesting for some time. Yes, dirt for a substrate is great for exercise(burrowing). But if you ask me the right question, should you use dirt with a hatchling, I may not give you the answer you want to hear. I would say yes, if you already knew the right type of dirt, but if you have no idea, then I would say no, take a different approach. You see, the wrong dirt for hatchlings is a quick death. Baby anything, do not have the ability to withstand our goofy errors. And surely giving them the wrong dirt is goofy, to them.
About the Retes stacks, Robyn had nothing to do with them, he simply borrowed the idea from us. We used them before Robyn knew what ackies were.(no offense, please). But I don't mind as I like all inventors, borrowed the concept from someone else. I just don't know who. I burrowed from the fella or fellas, that kept pilling tin and wood and other such garbage all around nature and the edges of nature. You know, the places one would go to find snakes and lizards. Those snakes and lizards use trash piles(tin, wood, etc) for the exact same reason and intent as a captive reptile uses Retes stacks, thermoregulation, moisture controll, and security. Yes, I used them with colubrids and pythons way before I knew what an ackie was.
By the way, if you really want to break your bank, as you said, then you may consider getting two or three ackies, because if you asked around, the real joy in keeping ackies is watching how they interact with eachother. The deal where they constantly put their arm about the other is amazing. Also, because they are insect feeders, its just as convient to have two or three as one. Sometimes way cheaper(buying insects in bulk).
So good luck and save your verdict for later or just can the verdict, as most likely you will not keep them long enough to have one. FR