Hi Lacie
Here are my thoughts:
If a punter is coming to you for mild or light bondage, probably a pair of those furry cuffs and a very lightly applied whip is what they are after. To my mind, that is not BDSM, it is just a little experimentation, to see what they might like to play with later and if in fact they might like it.
Further, I don't think that a Working Lady who offers mild or light bondage is that interested in BDSM. It is more likely she is just trying to keep her customer happy, or experimenting herself. She may even feel a little uncomfortable with it and not too keen to go further. However, that is OK and is a legitimate service to offer. Nothing bad or sad about that.
BDSM is all about going further. As Miss Minsen says, find his/her hard limits and work with them. BDSM is not a fetish; it is a life style. If you specialize, then you call yourself a Mistress, a Dominatrix, or a Cuntress (a la The Cuntress Gabrielle of Purple Palace fame, in Adelaide - That was a ride) However, if you do it, do it on purpose. Please don't advertise as a Mistress and then pull out fluffy handcuffs. I once visited a Mistress who did that. She also kept asking me what I wanted her to do; don't do that either. You are in charge. He/She is your slave and needs to be taught respect.
Here endeth the lesson