The problem is finding tubs with the right dimensions economically. ARS or Freedom Breeder are probably the best source for those for ones that don't waste a lot of vertical space for terrestrial snakes. There used to be a few companies that made economy racks with the tubs made by ARS/FB, but I think covid knocked them all out of business as far as I'm aware. You might have to save up money to get a rack from ARS/FB, or buy the tools and learn how to make your own and just get tubs from them. I think in the long run, ARS/FB racks are well worth the money because they last a lot longer, but they are a very pricey investment.