I manage a hair salon, we have had, on occasion, clients with such severe body odor or lack of hygiene that my staff is near vomiting, and we've had to leave the door open to air out the salon. I don't want to cause a scene or embarrass anyone but I also don't want to loose other customers.
Evan: Take the smelly would-be customer aside, and tell him or her that you are unable to give salon services to people who don't take sufficient care of their personal hygiene.
Better to insult one undesirable customer than to drive away other good customers.
Many such people are genuinely unaware of how bad they smell. Lack of good bathing and/or laundry facilities, or the inability to smell themselves, are the usual culprits.
In the military, where men are housed in close quarters, there's often the problem of the one who won't bathe. It's been known to happen, that a bunch of guys forcibly frog-march him to the showers and scrub him down with lye soap and a stiff brush.
Be honest and tell them the truth. They can't sue you because you have to work and not get an illness from your customers.
you might ask the person to accompany you to the back of the shop, maybe under the pretense of showing them something of interest, and quietly tell them they are not welcome in your shop and open the back door for them to leave
Are they pre- booked or do they just turn up on spec?
Walk-ins you can just decline.
Pre-booked, you'll just have to deal with it this time, and make sure that if they call for a follow up appointment, you find a quiet time in the salon to call them back and explain that customers' complaints about their BO, mean that you must decline their booking unless they ensure it doesn't happen again.
Tell them no appointments are available, or if you don't find out util they come in, that someone is sicck today and you're unable to serve them.
Yes, you have the right to refuse service to people that can present a hygienic problem. They could possibly transmit disease or lice.
A business owner should know that it's lose other customers and not loose other customers.