To enter Tradesperson's tools expense in forms mode of Turbotax desktop, open the form titled "Other Employment Income and Expenses".  On page 2, you'll find the "Tradesperson's tools expense" table.

Enter the total cost of eligible tools under the GST or HST column (this depends on your province of residence, and is used to calculate the GST/HST rebate, if you are eligible to claim).  

In the section below, enter your income from employment as a tradesperson for the year to calculate the maximum deduction for eligible tools, which will populate to line 1770 on the T777.
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