I do not sell my eggs that are extremely dirty, just because someone will complain, and mess the eggs up by sanding them or washing them. I set them with caked on poop and mud and get over 90% hatches. Weather you wash them or sand them you will damage the bloom and reduce your hatch rate. I had a first time customer that contacted me asking to buy eggs because he was getting zero hatches from his other sellers. I had him explain his ritual and sure enough he was washing the eggs before setting them. Arrrggggg... I told him I would only sell him eggs if he promised not to wash them in anyway, he finally got a good hatch.