I've had my two girls for going on three years now, so I'm a relative newbie to the whole chicken-keeping thing...but they are definitely worth it!
The biggest reason I got chickens was for the eggs. I have a difficult food allergy, which causes me to not only react directly to the offending food, but causes me to react to animal products if the animals they came from were fed that food! With my chickens, I have 100% control over the eggs I use, and I know they are safe for me to eat. That alone makes owning chickens worth it for me.
I don't find them to be any more work than my cats, and certainly a lot less work than my many fishtanks. They are, however, a DIFFERENT kind of work, which is probably an obvious thing to say, because they're an entirely different sort of animal! But they are really funny creatures and I enjoy them a lot. They've definitely got unique personalities and they are a lot more endearing than I thought they'd be!
The one thing I wasn't prepared for was how much they dig. I've got so many holes all over my yard now. So if you're someone who is super picky about their yard, or has someone around who could seriously injure themselves if they trip in a hole, then you may want to rethink chickens, or at least be considerate of where they're allowed to roam. I don't mind it too much because I'm lazy about my yard, but it does sometimes interfere with the ease of rolling their coop around.
The coop is definitely a major expense. If you're a DIYer, you can find countless guides online for all sorts of DIY coops.
That being said, I'm on DIY coop #2 and I am definitely going to pay someone else to make one for me next time

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