Tipping for hair trial and wedding day???

Hi girls, if you are going to their place (not a shop) and getting your hair and make-up trial do you tip the girls? And if so, how much $$ I really have no idea. Someone told me if is their OWN business then you do not tip. If you go to a shop then you tip??? I want to make sure I do the right thing.

Also, the same question... for the wedding day, do you tip in addition to what you are paying them? and how much for hair girl and make-up girl?

Thanks so much for your advise!