Setting a Master Service List item as 'Taxable' is easy:

​Step 1: Go to Settings > Master Service List

Step 2: Click on an item in your master service list.

Step 3: Select the 'This item is taxable' box.

Step 4: Save
​

Step 1: Tap on Menu > Settings > Master Service List

Step 2: Tap on an item in your master service list.

Step 3: Tap "This item is taxable".

Step 4: Save
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