I have a different point of view on this....you can get a very cheap stainless stock pot at a discount store for maybe $10, a thermometer for about $3-5, scrounge a plastic pitcher to mix lye in, and use a sturdy cardboard box lined with freezer or butcher paper as a mold...or as I do, a plastic storage tote. I trim off the ridges with a vegetable peeler. I use re-purposed plastic containers in which to weigh everything, and then you need a small kitchen or postal scale....often someone you know will have one you can borrow in exchange for a bar of soap. I was given two for free over the years! Yay!
I render tallow from grocery store suet ($0.89 per pound, with little waste...no waste, really, as I feed it to the hens) and use whatever other oil was on sale...various veg oils, and the latest two batches I actually used EVOO to make a special soap for us and a client who will pay the extra.
I make 24 bar batches and each batch costs me $11-15, including the lye. I don't count the goat's milk, as I save it up in the freezer if I have to deworm or if I just have too much in the fridge and it will end up being fed to the hens.
I don't scent mine and people will sniff deeply and exclaim that it smells so good!

Anyways, my basic soap costs $0.50-0.70 per bar to make.