I have 2 rental properties. When filing, do expenses e.g. supplies need to be separated PER rental property or can a percentage be assigned to x and y properties?

You will need to accurately assign dollar amounts to the expenses for each property separately. 

As per the Canada Revenue Agency (CRA), you have to keep records for each year you claim expenses.

It is best to not mix these up in case the CRA asks to see them.

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