|I'm sure that you are not going to charge to do this on a live system before you have practised on a test sytem. You need to be sure that you know what you are doing, any potential pifalls, and have a documented procedure to recover from any problems. Use this to estimate how long the procedure takes and then adjust your price accordingly.|
Uphrading a server system is obviously a greater responsibilty than upgrading a workstation. Be sure that you know exactly what is required before you start and the possible impact on any client machines. And make sure that you have a restorable backup, inluding Active Directory, before you do anything else.