You'll probably end up integrating at some point.
What I do is I put a wire dog kennel inside the coop. I wait until the youngest of the new group is fully feathered at around 6 weeks. I put the new bunch in the dog kennel inside the coop as a barrier and they have a chance to get use to each other. I keep them inside the kennel separated until the youngest of the bunch reaches 3-4 months of age or same size, which is about 6-8 weeks. I then put the young bunch on top of the roost.
This has gone very smoothly. I've integrated 2 times and now am on my 3rd round. We originally were going to have 2 hens. We ended up with 3 then 5 more last year equalling 8. I took out two of that flock and added 3 that I bought this past March. Then my neighbor wanted me to hatch chicks for her and she changed her mind once they hatched last week. I have 3 mixed breeds in the house, but I do think I have at least 1-2 boys in the bunch. My kids are attached to the hatched bunch, but I refuse to keep the boys. The rooster was not nice and his mean genes will pass to the boys only. I'll keep the girls and rehome the boys if they seem to be nice. I can not rehome if I know they will attack.
I'll most likely hatch in the future. I'll buy eggs from here or on
eBay. I like both crosses and pure bred. We live on 4 acres, so it's in between suburb and country. We are allowed roosters, but I have 2 neighbors who hate chickens.
I've tried talking my husband into moving on a bigger piece of property or a farm, but the housing market to sell is not good. We'd be losing a lot of earned equity on our house, so we will fence our property next year. Maybe I'll get a rooster after we finish fencing.
My neighbor across the street has a rooster and with my windows closed, I can not hear him. He crows all day long I guess. Her last rooster didn't crow as often, but he was mean.
I'm sorry they don't take the chicks back. It's very unusual to get so many boys in sexed bins.
My RIR was pretty mean until she started to lay. I almost rehomed her. I'm glad I didn't! She lays very good eggs! I'd love to have another, but I'm full in my coop. With the 3 downstairs we have 12.