Different webmasters, digital agencies, IT providers, and others you might hire to assist you are likely to have different rules when it comes to service accounts and who can access them.
My preferred approach is to manage service dependencies that generate portable data in my own service accounts (rather than in client accounts). For example, domain names, DNS records, certain types of hosting configurations, and many other dependencies can be thought of as portable because they can be moved from one account to another without loss of history or any other aspect of these assets.
Of course, not all services used by client projects work in this way. Analytics services, payment processing services, and print-on-demand services (to name a few examples), usually generate critical records like traffic states, orders and other transactions, incident cases, and other histories that cannot be moved from one account to another. In these cases, it would be problematic at best for me to use my own agency accounts for client projects. If a client becomes interested in making a change that is incompatible with my process, the project could suffer. If a client decides to transfer servicing from my hands to someone else's, critical data will be lost. In cases like this, when the service in question generates non-portable data, I never use my own service accounts to manage project dependencies. Clients are generally required to have their own service accounts in these cases, though there a few rare exceptions (imagine clients that care more about making sure their business is in front of your face every day than about their own activity history).
So why bother at all with categorizing service accounts in this fashion? Why not have all accounts run by the projects' owners? Two reasons:
- Time is money. Managing multiple accounts of almost any type takes more time than managing one. Some service account types actually introduce very significant administrative overhead with various tasks that need to be performed regularly. When your agency saves time by managing some of your assets in their accounts, they can justify charging you less.
- Safety and stability. Many service dependencies have critical impact upon the stability and quality of the project. Your project benefits greatly from having seasoned professionals attending to your more sensitive assets. Managing these assets within agency accounts instead of directing the agency to handle your own account, when possible, effectively guarantees that no one else can damage your configuration (it happens, sadly, and frequently, even with the best of intentions).
My own preference is to manage as much as possible from my own accounts. If a project requires me to manage all assets within project accounts rather than my own, I will charge for the extra time, and I will not guarantee stability of assets over which I cannot maintain absolute control.