The value of eggs depends on the value of the breeder birds, which is highly tied to the experience of the breeder and criteria that s/he uses for breeding. If this known breeder sold you a selected trio/quad, etc, (in other words you are using birds that an experienced breeder let grow up and then evaluated their characteristics to be sure that the cock and hens were all breeding quality and an appropriate breeding match), then there will be significantly more value to those eggs than if you simply obtained eggs or chicks from that breeder and are doing the breeder selection yourself. This is because your experience at selecting breeders will not be the same as the known breeder, and therefore is less likely to produce chicks of the same quality. It is important to realize that even for breeders with excellent quality flocks, the majority of chicks that they hatch will not breeding quality, and should be used for either layers, meat, or pets, but not breeding. Alternatively, many breeders will hatch out hundreds or even thousands of chicks and look for any little reason to cull them every week so that they don't have to raise as many to adulthood, but because they are breeding such large numbers they will statistically hatch out a few really superior birds. The reality is that few really experienced breeders will sell eggs or chicks at all, as they want to evaluate each bird and keep the best for themselves, sell the secondary breeding quality birds to prospective breeders, and then do whatever they do with the majority of the chicks (>90%) that aren't breeding quality.
But that's not what you asked -- that's just to try to give you some perspective. I am a preservation breeder of Red Dorkings. Most of us breeders know each other, or at least know of each other. We rarely sell eggs to the general public, but those that do typically sell them for $20-70 per dozen, depending on the quality of our breeder birds and the fertility rate of the eggs. If your are NPIP certified and shipping is needed, it is typically an additional $20-40, and it is worth it if the eggs are properly packed, because packing eggs properly for shipping is neither easy, quick, or cheap to do. Improper packing is easy, quick, and cheap, but also not worth doing.
If you do decide to sell eggs, a huge word of advice.
1) Do test hatching in your own incubator or under broody hens regularly, and let buyers know what hatch rate you are getting. Emphasize to people that hatch rate will not be 100%, but that you are getting XYZ rate using your incubator or hens.
2) Emphasize to people that while your hatch rate is XYZ, you have no control over their egg handling or their incubator, and therefore you are not responsible for their hatch rate if it is lower than that, or even if it is zero.
3) Set a policy regarding what you will do if people get a poor hatch rate and want you to replace the eggs. Obviously, you want people to know that you are not responsible for their hatch rate, but there will still be people that will expect you to refund the cost of any eggs that didn't hatch, or to replace any unhatched eggs for free. Most egg sellers will not refund or replace eggs at all, or will replace them at half price, or will replace them only once, or will not replace them but will instead sell them day old chicks at a discounted price, or something along those lines. Every seller has a different policy. It is important for you to consider this before the complaints come in, which they will, so that you can be prepared with an answer that works for you, and you can have consistency between buyers.
Good luck. I hope that you are able to breed some great chicks, and that you enjoy your egg/chick selling experience. I would also recommend that you join one of the FB pages that relates to egg selling so that you can read people's complaints and get prepared for what can happen. Many of these situations do arise because the seller made mistakes, so you can learn to avoid those problems once you become aware of them. Many of these situations arise because buyers can be ridiculous, unreasonable, and demanding, and reading those posts will help prepare you for handling those people too.
