Find a couple canning jars at the thrift store in two different sizes that would work as hand soap dispensers for the bathroom and kitchen. Choose a basic glossy white spray paint and spray it on the outside of the jars. Then take a nail and hammer it into the center of the jars' lids to start a hole. Use needle nose pliers to pull the tin back enough to fit the soap dispens...
Keep the mess in the towel then throw the towel in the laundry when you get home from your trip.
The Duggars' Homemade Liquid Laundry Detergent - $0.01 / load....hmmm, lots of good reviews on this. Maybe I will try it. Maybe.
DIY: Home made body wash-- Made 8/12 fairly successful...FYI using dove beauty bars turns out a very thin liquid. the best consistency was from the cheapy soaps I found at the dollar store. However, the Dove feels much nicer on the skin than the dollar store brand...what a conundrum! Will be experimenting with different brands in the future.