Advantages and disadvantages of yeast fermentation?

You mean like bread and rolls? Advantages: homemade breads are potentially really good (assuming you know how to bake), they're less expensive on a unit basis, and they make your house smell very good. Disadvantages: you've got to buy a lot of ingredients to make them, it takes a lot of time to do it, and you have to eat the stuff right up because it goes stale faster than store-bought.