You can’t please everyone all the time. And you need to know what you can and cannot do. Check out this sales tip from RAB.com:
Don’t be bullied
Sales trainer/motivational coach Paul Cherry
Stand up to bullies, even when they’re your customers.
Some customers just don’t deserve your business; they end up costing you more in time and resources than they give back in business and profits.
If you have customers who are bullies, confront them. If you can’t win with the bully because they’re their own worst enemy, or because their values are so out of sync with your own, walk away and invest your time on customers who appreciate the value you can bring to them.