Canadian Delivery Question?

Need some GOOD advice. Selling a car to one of our canadian members and i'm hauling it to the border for him. Border crossing will be one of three places. Detroit, Buffalo, or Lansdown, headed for Ontario. Never done this before so i need to know the ins and outs of this type of transaction. I understand that the requirements at each location is different. Gotta get it right. Title has to be there 3 days before crossing? What other paperwork. I guess one will need a passport for crossing? My brother will be doing the delivery and does have a passport. Tell me what you know. Would it be better for the new owner to come on the U.S. side for exchange? What will they ask at the border? What will they require and what will they want to know? Are they tough to deal with? Are they jerks? Thanks guys in advance? I'll check back in the morning. PM me if ya need to. Thanks
Small Block