[mklepaczewski]

tl;dr 95% yes, 5% no.

I'm a solo freelancer and I work from 8am till 3:30pm. However, there are times when things need to be done during late night hours. This happens maybe once a month and I don't complain - this is a bonus of working with me. When my client starts to abuse my flexibility I charge 2x/3x hourly rate for the tasks done outside my regular work schedule. This quickly verifies how important these tasks really are - sometimes clients indeed pay extra without fuss, at other times the "unacceptable 3 min downtime at 8am" becomes acceptable to them ;-). Share the pain with them.