Based on the information you have provided, the rebate should be included in the purchase price. Just like real estate commission is accounted for at the time of home sale, real estate commission rebate should be accounted for in the Adjusted Cost Base (ACB) at the time of sale.
Here is a CRA link that can be helpful: https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/about-your-tax-return/tax-re...
Thanks!
