Chinese geese are one of the smaller breeds and generally lay longer and more eggs than other breeds. Generally they will start laying in Jan or Feb and continue until early summer. I have heard that 30 to 50 eggs is normal total per goose. Things affect that - if they go broody and raise some goslings, etc. They generally lay one egg every other day. I am not aware of any goose breed that lays an egg every day.
Like someone mentioned, prices vary from inexpensive "sale" goslings to the higher priced "show" quality ones. Most hatcherys have the chinese in the spring when it is the laying season for geese. You could check swaps and local advertising sites for goslings and adults. Goslings generally will only be available in the spring.