If i have adword account in my personal name. so is it possible for me to post ads for others, and charge my consultation fee? Or i will have to open seperate accounts for every client?
Separate accounts linked in your mcc- doing it any other way will just get messy. http://adwords.google.com/support/aw/bin/answer.py?hl=en&answer=7725 Edit - EEK! just seen that you're the same poster that was asking what the Quality Score is - http://forums.digitalpoint.com/showthread.php?t=1477411 How have you got the nerve to charge people money when you don't even know the BASICS?
If you want to charge people for managing their account, you should first learn what is Adwords all about and get some experience with your own account and website... and finally study to pass the Google Adwords Exam.
You can use your own account without a problem. I would however strongly suggest that each client have their own account. This way, you charge only for your service and don't run the risk of getting stuck with the click costs should they skip on you. You can link all your client accounts to yours. You can get a My Client Center (MCC) account to do that. It will make managing many accounts much easier.