We're the ones who refill the liquid soap bottles at least a dozen times before we replace them! I've tried refilling the bottles for liquid soap with body wash (which was about half the price, at the time), but it was too concentrated. So we're back to refilling the liquid soap dispensers from the jumbo-super-economy size bottles.
For the foaming soap, though, I came across this tip on another blog--I forget which one!--and I've been using it regularly.
When the foaming-soap dispenser is empty, remove the cap. To the empty bottle, add about one tablespoon of body wash. (I've also used liquid dish soap, but the body wash gives better results.) Slowly add enough water to fill the bottle about three-quarters full. Replace the cap (or hold your hand over the bottle opening) and shake carefully. Replace the cap, if you haven't done so. Press the pump a few times to prime it, and you're ready to go.
This body wash, even when it's not on sale, costs about $3.00 for 13.5 ounces. If it makes 25 refills, that works out to about 12 cents per refill. It's not the best for greasy hands or after handling raw meat. But for most of the times I wash my hands in the kitchen, this is what I use.
Do you have any tips for saving money on everyday basics like hand soap?