It's also very important that you ensure all the ingredients in the soap are suitable for skin application. For example, some candle fragrances can be used in soap, but not all of them. A good example is cinnamon, which some people have allergies to.
The most expensive soap you could make would probably involve natural additives like lavender essential oil. One of the advantages with soap making is that until you get into the specialty stuff, you are basically looking at the same price structure. Goat's milk, coconut milk, hemp oil, olive oil, and shea butters are all fairly inexpensive soap additives.
Soap making is a great crafting project for families, boy scout troops, girl scout troops. It's fun and what's best about it is that you start a project with some raw materials that don't look like much and in the end you are going to have something that's useable and that the kids are going to enjoy for a longtime. It can also be a great strategy for a kid who doesn't like taking a bath. Having made their own soap adds an element of fun to bath time. And there's also a sense of accomplishment at having made your own soap.
One fun project is always soap on a rope. You make a U-shape so both ends of your string fall into the mold and your pour the soap around it.
Another idea that's unique is layered soap where you pour a couple layers of red, then white, then blue. And the layers can have different fragrances. Maybe cranberry, vanilla, and blueberry. And you get exposure to all those fragrances each time you use the soap.
