Well i think Anything strong will do, I built mine and love it. it came to around $275 And that may seem high but it holds 13 reptiles for me. (or more if i change the bins around) However i use mine for my snakes. so if you replaced it with just leopard gecko bins. your looking at around 18 BINS * for adults* , now thats nice. and it was pretty easy to build. took me 2 days for everything. So i would say by far home made are the best. but you can buy one. but your looking at a very big price tag.
here is a photo when i first made it, If you would like to see building photos. (in case you would like to make one) just mail me.
I built my own as well. If you search, you will find TONS...that people have designed and built themselves, as well as ones you just buy and assemble. Here is my thread about the one I built, all information is in there: