You are entitled to deduct the cost of your home office
If you operate a business from home you are entitled to deduct the cost of your home office for Canadian Income Tax purposes only if a separate part of your home is used to carry out the business.
Writing off rent related expenses for home based corporation
For a home based corporation to write off rent related expenses you have to charge "rent" to your corporation. The amount is taxable to you, but will be offset by the equivalent amount which you have paid such as utilities or property taxes.