There is a range of rebates related to new housing. The most common rebate is the one for new housing bought from a builder. If you want the GST New Housing Rebate (with a provincial rebate portion, it can be very valuable), you must meet two main conditions:
(1) When you sign the agreement of purchase and sale with the builder, you must be buying the house (or condominium unit) for use as the "primary place of residence" for you or one of your "relations" (e.g., siblings, parents, children, grandparents or grandchildren). (2) you or your relation must be "the first individual to occupy the [new home] as a place of residence" "after substantial completion of the construction".
Mr. and Mrs. Napoli said they originally bought the home for her parents. But they agreed to rent it to an unrelated person within two weeks of agreeing to buy it. The tenant was the first to occupy the home as a place of residence. (The judge didn't believe the Napolis' claim that they or Mrs. Napoli's parents had used the home as a residence during the two weeks before the tenant occupied it: Paras. 8-11.)
So that was the end of the appeal: the Napolis failed the tests for the rebate and had to pay it back. But the Napolis also asked the judge to consider allowing them, instead, to claim the New Housing Rebate for landlords. This rebate applies to people who buy properties to rent them to individuals for use as residences for a rental period of at least one year.
The Napolis could have met the conditions for the landlord rebate but, like other GST new housing rebate rules, this has a two-year limitation period, which had expired by the time the Napolis realized they should apply for it, in 2011. (See Excise Tax Act s. 256.2(7)(a).) (Paras. 13-15.) (Generally the builder credits the rebate at the time of closing; so the 2-year deadline isn't an issue. Though the builder did credit the Napolis for the GST rebate on this purchase, the credit was for an "owner-occupied" home, not for a rental property.)
See Napoli v. The Queen, (2013 TCC Paris)