Rather than trying to play Chef Oscar, with a whole duck, I limit my purchase to boned Duck Breasts. That simplifies the buying problem, the cooking problem, and the serving problem.
Omaha Meats sells ungraded beef, and I won't buy ungraded beef. But when it comes to duck breasts, they have a real winner, they sell Peking duck breasts for something between $11-$14 each. Each breast is good for a single serving, and your guests end up with the prime part of the duck with no waste. Because you are cooking only one part of the duck, your cooking problem is simplefied.
I leave the preparation and cooking guidance to others.