I had good results with probiotic enemas as long as I used live acidophilus and minmal water.
I wouldn't recommend white vinegar, but apple cider vinegar absolutely, especially at the outset of a candida protocol. yeasties hate the stuff. :)
My favorite retention enema is liquid chlorophyll or aloe vera because they're so soothing. Baking soda is too harsh, don't like any salts really except for basic Sea Salt .
And instead of coffee, consider using Gotu Kola decoction - make tea and use that as the enema. Great stuff.