I always tip Beamer's groomer. She is mobile and comes to the house.
Heck, sometimes if it is a late appointment we have her stay for dinner
She is great - when I had the stroke a few weeks ago she came when I got out of the hospital and groomed Beamer and wouldn't accept payment. She even cuts Lil Bit's nails sometimes when she grooms Beamer (Lil Bit doesn't need grooming as often as Beamer) and doesn't charge me extra for the nail cutting.