Thanks to J.S. Klein for this Frugal Baby Tip!
I use baby washcloths too. My daughter's change table is in her nursery (might as well be as it's not like she SLEEPS in there LOL) so when I remember, I grab a cloth from the stash in the bathroom and run it under the warm tap.
If I forget, I have a squeezy bottle full of plain old water that I use to wet down a cloth from the stash on the change table. I've never found that we need anything other than water, to be honest.
I have seen that Kissaluvs makes a "Lotion Potion" that you mix with Witch Hazel, which is supposed to keep nicely. I've been tempted a couple of times, but then I figure if it ain't broke...