A Good homemade soaking solution for sore/aching bones, joints, and muscles?

i have Spina Bifida, and of course, the aching joints, bones, muscles, etc, comes with the teritory. i've tried plain ol' hot baths, hot baths with epsom salts in it, and some soaking solution i found at the dollar store. none of wich really work. what i would like to know is does anyone know of any good, but CHEAP soaking solutions? home made or not doesnt really matter but it HAS to be cheap. i'm on SSI i dont work other then babysitting so i dont make a lot of money. so it needs to be cheap. that is all i care about (other then the fact that it needs to work GOOD!)