I've only hatched shipped eggs a few times. My average hatch rate for all of them was around 50%. One was 100%, another 20%, and one 33%. Not much of a sample size but an average of around 50%. You never know how many will hatch. It could be 100%, it could be 0%, it could be anywhere in between.
You never know what sex they will be. I regularly get hatches at 66% or even 75% one sex or the other. It is fairly rare that a hatch is right at 50%, but it happens. Some seasons I get hatches where for the entire season I get 65% or more of one sex or the other. When I average two or three seasons together I get close to 50% on the sex, the larger the sample size the more the odds kick in. There is no guarantee how many will hatch or what sex they will be.
How many eggs should you set? How many chicks of either sex are you prepared to deal with? You can keep them, give them to friends or relatives, try Craigslist or chat with your neighbors on your state thread in the "Where am I? Where are you!" to see if anyone will take them, advertise in the "buy, sell trade" section of this forum, or maybe chat with a zoo or wildlife rescue to see if their animals need a meal. What are you willing to do if you get great hatch?