Question:  query regarding duck  [ layer ] farming  
Answer:  capital investment , cost of [ construction of shed , ducklings , feed , electricity , & water supply , medicine , & vaccine , insurance , utensil & appliances ] are the prime criteria for a duckery unit , besides  the size of the pond& quality of pond water or water reserve  , location of the farm/ shed , direction of sunlight  plays an important role for a duckery unit