The other issue is that many of my good customers have done some of the things on the 'difficult customer' list. You can't easily pigeon hole customers as 'bad'

The other issue is that many of my good customers have done some of the things on the 'difficult customer' list. You can't easily pigeon hole customers as 'bad'. I have only had one REALLY bad customer - he tended to swear in his email (and his password was "fuckyou"), he used various aliases, and lots of people on forums said he basically scammed them. Also he was very rude and dumb. Anyways, I decided to charge him about 5x the normal rate (and he was too dumb to notice). This is the only time I've ever done this. Anyway, he paid for a year or two and then (thankfully) went out of business. However even my best (and nicest) customers do some of the things here...sometimes they give me a big long list of questions at their first contact, or persistently call if they have what they think is an urgent problem or question. Usually as long as they're not rude I don't have a problem with it, and they're normally pretty happy if I send an email saying I'll reply after the weekend or whatever.