Ive hunted the Deleware bay with some buddies. Not too far from the Chesapeake so Im sure the hunting is similar. We did a day of shore hunt for a mix of divers and black ducks, a day at Prime Hook NWR for greater snows and black ducks, and a day of layout for Old Squaw. If you've never done it, Id find a guide that focuses on open water layout hunting. It's a lot of fun and not something you're likely to find in our area.
Try to find a guide that hunts all day and not just a few hours in the morning. Large tide swings up there that can dictate when the birds move.
Just FYI, Im hearing that the systematic targeting by the guides has put a major dent on the east coast sea ducks and the populations have cratered, Flocks often don't have mature males because they all get plucked out so fast. Might ask for pics of recent hunts to know what to expect.