I normally work from 9 AM up to 9PM during EST. I do work on weekends if necessary and accept projects on a contractual basis with clear outlines.
For fixed contracted jobs I normally ask for 50% upfront and the remaining 50% when all worked has been view, signed off and approved but before the file transfer.
Any form of communication is fine with me so long as it is productive. If I feel that a form of communication is not working very well, I will suggest an alternate form. For example some people convey ideas better with speech or calls. Some people are difficult to understand when they speak and emails/text is optimal.
I use a stepping stone method that is greatly appreciated by most clients rather than coming up with one design from start to finish and then submitting it for review to find that the designer was way off track.
This peace of mind process always works.
The entire process summarized would be:
1) Accept job and start initial style designs
2) Submit for review and feedback to client (communication)
3) Clients returns with any revisions (communication)
4) If revisions, complete - Move forward to next section of project
5) Repeat with more designs until project is entirely complete