No one answered my bride question…
Ames, I recently asked my Rabbi about Maaser Kesafim. He said that you should be taking 10% from your after tax, before expenses money UNLESS you cannot pay your basic bills (like rent, food – zero luxuries allowed in there). I didn’t ask him for more details because we can pay our basics with some room to spare (after taking off maaser). But yes, its BEFORE expenses.