I believe your supposed to have the paperwork at the border 72 hours prior to bringing the sled back,actually this applies for any vehicle bought in the US,but if you don't plan on ever taking it back across the border you can get away with just showing up the day of purchase.You don't have to schedule any appointment or anything like that but you will need some paperwork.The bill of sale especially but if you can get it the registration too really helps,and be prepared to spend some time too because along with the inane questions they like to ask there's the RIV paperwork that you will have to fill out.RIV is Registry of Imported Vehicle and this is necessary to bring any vehicle into Canada.
I bought my 01 SRX a year ago October and just showed up with it at the border,all I had was the bill of sale which will pass for your documentation just be absolutely sure things like the date,purchase price,serial number and signatures are on it.
The border crew will ask some pretty numb questions too like where did you find the vehicle,ie Craigslist or other auto trader,so they can look it up and question you about the purchase price,especially if there's a big discrepancy in the asking price and your purchase price.They make you feel like a friggin criminal with some of the questions they ask.And be prepared to have them call the seller to verify the sale price to so if you do have the bill of sale wrote out for less than what you actually buy it for to save on the taxes make sure you and the seller have your story straight because it's not uncommon to have the border agents call to try and trip you up on the price.
Once you get the vehicle home you have a certain amount of time to have the RIV inspection done at Canadian Tire,unless there's another authorized inspection station around you to do RIV's.There's a fee for this too,naturally,something like $240 or $250 dollars,then it's just a matter of changing the vehicle over into your name and registering it.
You'll have to email Yamaha Canada and get a letter stating there's no outstanding recalls and other bs too,this you'll need when you get the RIV inspection done.It's free to,one of the only things that doesn't cost ya in the whole transaction.