1. Don't let the customer decide the deadline. 2. Don't accept to work for a fixed fee on code you don't own. It's per day or per week... and no promise. 3. Do

1. Don't let the customer decide the deadline. 2. Don't accept to work for a fixed fee on code you don't own. It's per day or per week... and no promise. 3. Don't answer the customer outside your open office hour. Put some strict limits about your availability. 4. Rise your fee. As others already wrote here, the smaller the customer, the higher they will feel entitled about your work. 5. Have a written contract. Don't accept close you don't like because "we never use them". 6. Be annoying about the description of the job, and the definition of done.