Here is how to change the price of an appointment, if there is only one service on the invoice:
1. Click on the appointment window
2. Select the Billing tab
3. Click on the pen icon
4. Enter the new price and Save
Here is now how to modify the price of a service found on an invoice with multiples appointments:
1. Click on the appointment window
2. Select the Billing tab
3. Click on Invoice
4. Click on the pen icon next to the item you would like to modify
5. Replace the amount under Unit Price for the desired new price
6. Save
