Mine is really basic and generic:
One of the two panels on the front of the house swings open as a big door. The pool will be getting replaced with a larger kiddie pool with a French drain system underneath it. The current one creates a giant stinky mudhole that the ducks love to play in...
It really depends on the duck. Spring ducklings will usually start laying the same year, unless they're a late bloomer. Summer ducklings will usually wait until the following spring... but again, it depends on the duck. I have four that are 9 weeks old yesterday, so I expect them to start laying...