Buying sets at the US retail price

[Gumby]

I managed to get a 10179 UCS MF for US$525 shipped to my house.

My in-laws were in Portland recently, and they called the day before to check store stock. The store had 1, but when they went the following morning, 2 hours after opening, somebody else had bought it! The store ended up ordering one for me at the US retail price, with free shipping (because it was out of stock), but I had to pay 5% GST (probably because the item was shipped to Canada).

I didn't pay any "duty" either; I think it's because the box went from their US warehouse to the CDN warehouse (in Ontario?) before coming out to BC.

By doing this, I suspect we're able to buy sets at the US retail price, and not get dinged any extra fees at the border.

I know stores offer shipping to your doorstep. Even if an item isn't out of stock, I wonder if you could use this service to get sets at US retail prices. In many cases, US retail price + shipping can be cheaper than CDN retail price + shipping.