For example, chicken coop, chicken feed, time to feed the chickens, time to go get the eggs, risk of chickens dying, smell of chicken sh%^, etc.
the coop is your only real upfront cost.
feed is only about $15-20/month. the range depends on winter vs summer and how much time they get to spend free ranging.
the rest of your concerns can be managed by setting your coop and run up properly. for example, my feeder holds 60lbs of food, so i don’t have to worry about feeding them every day. i use a deep bedding system in my coop, which means in about 18 months of having chickens, i’ve cleaned it out once and it doesn’t smell.
i have my coop and run set up so that i can go on vacation without a second thought as to whether or not the chickens are ok. i just hire my teenage neighbor to come grab the eggs every other day.
all in all, i’d say they take up less than an hour of my time weekly and i have 16 happy, healthy birds. it’s far less work than people make it seem.
i can put together a punch list for anyone considering getting their own chickens wirh how to set yourself up so that your coop and run are as self sufficient as possible.