As someone offering your services to a customer, you give a price, and the customer tries to bargain said price… that's just how it goes. It's a frustrating, but necessary, part of the job. However, when a customer attempts bargaining AFTER you've completed the work… well, that's a whole different story. After settling on a price, you shouldn't have to deal with someone who refuses to pay that cost. That is what happened to a contractor who collected rubbish for a customer who decided after the…