QB Issue Resolution:
In the US version, I hope it is the same in the UK
menu edit>preferences>send forms
Select the type of form from the drop down, then click edit or add new and create your own, the button bottom right allows you to insert fields into the text of the email not the subject line
Note that though you can set the default template to work within send forms, if you are using outlook to send the email, QB ignores the custom letters and always sends the built in default form – a bug they know about.
Resolution for Issue 'How to save a customised email text to different customers?' available: Yes (Solved).
Source: Intuit Community forum.
How to save a customised email text to different customers?: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for Customer
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