Is Indiana a title state? I know anything under 20ft in Michigan and there is no title. This is the stuff you need to figure out. You either need the title or something from a bank stating there are no liens on the boat. At the border you'll pay RIV and GST, when you register the trailer with the MTO you'll pay HST on that. Make sure you've got two receipts, one for the boat, one for the trailer (Obviously you want the trailer to be the cheaper one of the two because this is what you're paying tax on at the MTO)