For hourly project - we prefer to take the payment on weekly basis.
For Fixed Budget Project - the payment remains on milestone basis. We mutually agree on different milestones and based on the progress of the work, we ask for the payment release. We include one payment in starting and one at the end of the project. For making sure that we meet the deadlines - we need response to our question/doubts within 24 hours and would like the client to be available for Skype meetings within 72 hours from the requested time.