OK here are two of my tub-ups, first one is for my retis. Coir and peat mix with a handful of wood chips, couple of fake terrarium plants stuck to the side, an aquarium plant stuck in a plant pot using aquarium safe sealant, and a couple of plastic plant pots buried in the substrate, with organic moss over the top (got it from an organic farm). The retis are hiding under a plant in the corner, they're still not talking to me since I cleaned the tank out yesterday.
Next one is a DIY job for my Cepaea hortensis and nemoralis. I used two large Tupperware type boxes. cut the bottom off one box and drew around it on a lid. I then cut out a hole so the cut off bottom would sit flush onto the lid. I then sealed the two together with aquarium safe sealant. So the set-up is twice as high, with loads of upper space for the snails to climb about. Substrate is peat, set up has a piece of fake plant, two plant pots and more of the organic moss. Few beech twigs too.
3 communist Achatina reticulata: Marx, Lenin and Trotsky.