CRA notes that a fee paid for assignment of a non-builder’s new house purchase contract does not affect the GST/HST new housing rebate
The computation of the new housing GST or HST rebate takes into account the total taxable consideration for the supply of the new house to the individual purchaser. Where A, who agreed to purchase a new home from the builder, assigns her purchase agreement before closing to B for consideration representing the increased value of the underlying house, the new housing GST rebate to B will be computed on the basis only of the original purchase price – unless A also constituted a builder (e.g., A had entered into the purchase contract for the primary purpose of reselling the house), in which case, the assignment fee would be taxable, and the computation of the rebate would also take into account the amount of the assignment fee.
Neal Armstrong. Summary of 23 March 2017 CBA Commodity Taxes Roundtable, Q.21 under ETA s. 254(2)(i) and s. 254(4).