If you plan to raise young ducklings and goslings you need to be prepared.
They will need shelter and need proper housing as they will outgrow the little boxes you might bring them home in. They will also start to be messy, active, and smell.
After a few weeks, you will need to have quarters ready for them. You will need floor space for the first eight weeks until they have their feathers. This is needed to be ventilated as they give off lots of moisture these first weeks. To have them stay healthy you need a clean and dry area for them such as a small building. Also, they will need protection from other animals and the outside weather.
For the first few weeks, you will need a small enclosure with infrared lamps. You might want to separate the ones that will be used for brooding and the ones that will become meat ducks.
If you only are having one or two pairs of ducks you can use a small doghouse but you will need an enclosed area to protect them from predators during the night. A good bed of straw remains in the dog house will do fine even in the winter. You should build a pen around the dog house of one-inch chicken wire for them to get exercise and to be able to feed and water them. You want to water them outside the house as they will spill the food and water all over the inside of the house. You might even take space in a building
and use just a corner for them as after they grow you can move them to a larger space. You can also move the area outward as they grow.
If you make commercial housing it should consist of long and narrow houses that will be divided by short 12-20 inch plywood walls and each of these sections containing about 125 to 150-day olds.
You could put a canopy hover along the back length of the building to heat with hot water pipes for brooding. You can probably do away with the brooding heat by the third or fourth week if the weather is mild.
You would need an outdoor run for them from the time they are one day old to the age of taking them to market. These runs do not need to be very tall as they won't be flying constantly. You could use short sections of fence, be sure the fencing is 1 inch at first as the day-olds can get through a 2 inch spaced wire. I would suggest using a 20-inch smooth piece of plywood as a barrier to making a run for them.
You will be able to see the difference day by day as to growth and be able to best determine the needs of these ducks and goslings as to the height of the wire, the plywood barriers, and space they will need to grow to maturity.