A milestone party needs a steady hand behind the bar so you can actually talk to your guests. Booking a pro is the best way to keep the drinks flowing without spending your whole night cleaning up spills.
Weekend dates fill up months in advance, so lock in your talent early. Once the booking is confirmed, you can map out the payment over a longer period to keep your cash flow steady.
Remember that the 0% period is a deadline, not a gift. If you still have a balance after the 18 months are up, you will start paying interest on what you owe.