Hi Jean,

Thanks for using Sage City.

There are several different templates available within Sage Accounting for invoicing, for you to view these go to:

1. Settings
2. Click Business Settings
3. Select Templates and Logos

From here you can select the template you want to use for your invoices, for more information I have attached a help article below so you can see what changes can be made.
https://gb-kb.sage.com/portal/app/portlets/results/viewsolution.jsp?solutionid=222001000101144&utm_source=findbytag

If you do need to change invoice templates depending on who you send your invoices to, unfortunately you would have to change the template each time before sending it out, there is not a way to have a template specifically for that customer. If it is something you would like to have use of in future, you can leave feedback back within the Sage Accounting product, by following these steps:

1. Click Help
2. Click Give Feedback
3. At the bottom of that box select "Share an Idea" 
4. Click Add a new Idea and fill in the details
5. Click Share idea

If this helps, please click Verify Answer.

Regards,
Stuart
Sage UKI