Most of what I have been hatching is shipped eggs. Thereās been various problems from various different aspects, from the sellerās end all the way through my end through hatching. Overall, though, I will continue to hatch shipped eggs to get the breeds I want (space pending!) and overall have been rewarded.
I would NOT spend $200 on chicken eggs though!!
I havenāt found a difference between Spring-Summer-Fall and hatchability, though realistically I canāt rule it out either. If anything, the incubator doesnāt have to work as hard to maintain temp, and high heat doesnāt affect downy chicks like grown feathered adults (those are miserable unfortunately)
Most of mine come from
eBay. No sellers have been bad per se, but there are some I wouldnāt buy from again for a few reasons. Really scrutinize them and the images they put up. I have decided to not buy from anyone less than 99% rating. There are some really great sellers though, too!
As far as fertility- there is no way to tell looking at an egg whether it is fertilized. Even if itās fertilized, there are so many things that go from fertilization to chick. Most breeders can say pretty accurately an egg is fertile, because statistically if the fertile disc is present in x number of eggs they open up and/or x number of eggs are hatched, and they have a bigger rooster to hen ratio for breeding, they can say they offer fertile eggs. I can say I have fertile eggs, because just about every egg I open to eat has the bullseye disc! Unfortunately, you will not be able to open a ādudā after attempting to incubate and locate a fertile disc. It disappears after a while so you canāt say itās a dud because itās not fertile or some other issue.
I guess very general advice - 1) consider why you want to order shipped eggs. If you just want to experience hatching and breed isnāt a concern, find something local. If you are trying to get specific breeds and live chicks are like $100 a pop ā¦ yeah get the eggs. And expect some expense (but not $200!). 2) Have you hatched eggs before and have a reliable incubator with all the kinks under control? If not, I highly recommend trying local eggs first before killing off expensive shipped eggs because some hatching variable was off (yeah, Iāve killed some eggs and learned some things). 2) Whatever you hatch, you
must have a plan for males, because you
will get them if you hatch anything. 3) For shipped eggs, expecting a 50% hatch rate is pretty decent. If you get a higher hatch rate, be pleasantly surprised! 4) Getting eggs shipped from somewhere closer to you as opposed to across the country does
not correlate with less PO damage! I can attest to this - it seems my less damaged eggs come from farther away rather than from states right next door! 5) Look for that NPAI or whatever that health certification is. It means more in some states than others, but at least itās a tiny bit of guarantee - just a little - on flock health, and means the breeder is at least somewhat serious to have gotten their state out to their place to take a look. Itās not a guarantee for perfectly healthy and husbanded chickens, but itās something.
Or are they just assuming? I know there's no 100% guarantee on hatching eggs, so I'd love some advice before either making a 4hr road trip or spending $200 for ONE DOZEN eggs to be shipped. 
From watching my own flock, I totally understand. It's been 100Ā°+ lately & everyone has been tired from the heat. 
In my last batch of chicks, we had six out of ten end up being roos! 
