Capt. John beat me to the answer, LOL. It's best to pay in full, but not everybody is in that situation. If you have good credit, you shouldn't have too much problem getting a loan of 20 years, but the interest rate will NOT be like on a home at 4.87%. I would expect in most cases a rate of 7.5-9.75% APR. I paid for my new yacht "In Full" so I have no payment and the cost is the lowest.
40+ yrs boating experience, Boating Safety Instructor, member of United States Power Squadron, owner of 60' motor yacht and 26' Express Cruiser