Unfortunately you cannot deduct the cost of your laptop purchase as a Commission Employee. The following information comes from the CRA Employment Expense Guide (here's the link: https://bit.ly/2Tt9PWZ).
Computers, cell phones, and other equipment -
If you lease computers, cell phones, fax machines, or other equipment, you can deduct the part of the lease cost that reasonably relates to earning your commission income.
You can also deduct the part of airtime expenses for a cell phone that reasonably relates to earning your commission income. However, you cannot deduct amounts you paid to connect or license the cell phone.
If you buy a computer, cell phone, fax machine, or other such equipment, you cannot deduct the cost. Also, you cannot deduct capital cost allowance or interest you paid on money you borrowed to buy this equipment.