Can I add all expenses from one supplier together or do I have to record each purchase seperately?

This is regarding renovation expenses.

After you file

You can add all the expenses from the supplier, but you should make sure that all the expenses from that supplier are tax deductible. You should also keep in mind that you should separate any HST/GST from the bill since the HST itself may result in a rebate. If you'd like to know more about claim expenses for small businesses, here is a great article by TurboTax. 
 
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