I would like to switch to quickbooks accountant. That is the reason why i signed up with quickbooks to prepare accounting services for clients.

Welcome to the Community, @adrianrblackman.

I'm here to help ensure that you can sign up for an accountant version of QuickBooks. 

You'll need to cancel your current QuickBooks account and sign up to the accountant version.

To cancel your account:

1. Log in to QuickBooks Online.
2. Click the Gear icon.
3. Select Account and Settings.
4. Choose Billing and Subscription on the left.
5. Click Cancel Trial.
6. Select Continue to Cancel.
7. Answer the exit survey and choose Confirm Cancel.

The following is a brief video to serve as an example of this process:

For more details about cancelling your account and what will happen to your data, please see this article: Cancel your QuickBooks Online subscription.

Once done, you can now sign up for the QBO Accountant. This way, you can offer services to your clients. Here's a link that will guide you all throughout the process: QuickBooks Online Accountant.

On the other hand, know that QBO has the option to invite you as the accountant of your client's file. All they have to do is to add you as their accountant in the company and work with their QBO.

To do that:

1. Click the Gear icon in the upper-right corner and select Manage Users.
2. In the Manage users page, select the Accounting firms tab.
3. Click the Invite button.
   
4. Enter your accountant's information and click Save.

To learn more about this, see this reference: Learn how to add your accountant in QuickBooks Online.

I'd be glad to answer any additional questions should you have any. Best regards. 

@adrianrblackman 

Where are your clients located? QBO Accountant is only available for a few limited regions.