Welcome to BYC!
Posting your location might help people give you more relevant advice.
I LOVE my Cayugas. I have two females from Meyers Hatchery (almost 2 years old) and two females from Holderread-line eggs from
eBay that I hatched out under a broody (almost a year old). One of the Holderread girls even lays black/gray eggs! I hope to get more eggs from that seller this year maybe.
Marketing your ducks is going to be different depending on where you live. In some areas, buyers might prefer any of the following: eggs for eating, fertile hatching eggs, day-olds, young ducklings, ducklings that don't require heat anymore, point-of-lay females, excess drakes for meat, breeding pairs/groups, even collected molted feathers! Your market preferences might even change depending on the time of year, like young ducklings being more popular around Easter (unfortunately), or excess drakes for various holiday dinners.
You WILL have to figure out what to do about the excess males, like it or not. Too many males are too hard on the females and you won't need very many males to take care of the females. And if you want to even
approach the concept of not losing $10 for every $1 you make, you will not be able to keep all the males. This is me telling myself this, too! I LOVE my boy ducks and roosters and I do have an all-roosters flock (grow-outs, breeder back-ups, and a few "pet" roosters) but I just can't afford to keep feeding a bunch of freeloading extra males that aren't contributing in any way except eye candy. And trying to find "pet homes" for every excess male you hatch out just isn't practical or realistic because most people want
at most one male duck for every 3-5 females, and that's if they have only one male.
When we bought our farm last summer, I had planned on selling eggs for eating. However, I've received a lot more interest for babies, pullets/young layers, and males for butchering than I have for eating eggs, or even fertile hatching eggs. So I bought an incubator, borrowed a couple, and started hatching.