Canadian here as well. I flipped a couple of contracts end of last year/beginning of this year and hired a US tax professional to handle it for me. There are a number of individuals who do this and your broker can recommend some but I used Wade Johnson (it's who
DVC Resale Market recommends). Everything went smoothly but it does take a while to get the refund. My sales were last December and then January and I got my refunds in November.