Dirty eggs are unavoidable and should be cleaned when possible. A chicken will not lay forever, and there comes a time when the egg production drops to an unacceptable level. Farmers will cause their layers to molt after approximately fourteen months of production. An alternative is to introduce new birds regularly and cull older birds. Your particular circumstances will determine how best to go.
Egg production is a long-term commitment.
For best results, you need a regular clientele. Egg production should occur throughout the year. Once established, a farm can make a healthy profit from the eggs. Many people also find that chickens are fun animals and can even make wonderful pets. My hens also ate some of the eggs.