Let me start with I DON'T KNOW: I do know that's a tricky situation for most of us ordinary T-Tax users.
My first guess was that Yes, it was money you received and even though it was a rebate it was a payment that had probably been reported as part of the cost of selling the house so a reduction of taxable income. But upon closer reading I think the particular details of the sale, the tax, and the rebate might suggest otherwise.
I have a somewhat similar
situation
pending
with a
rebate received in 2017, that I thought might require an amended return for 2015. A T-Tax expert says No, count it as regular income for 2017, but I am going to check with IRS ASAP as the confusion arose on Friday evening. I recommend that you do the same.