It isn't the quantity.... a single hen will be enough to alert your neighbors to their presence. They're not usually all loud at once, they're happy to take turns.
My very first flock was in a nice subdivision on a cul de sac. Fortunately, we didn't have a HOA to contend with. The city allowed chickens if your coop was 100 ft away from your neighbors home. I had exactly one spot in my backyard that could meet the requirement so that's where we built. Our coop was very nice-we spent a lot of time on it and quite a bit of money. It was important to make it "fit in" with the neighborhood and have it not be an eyesore. We had 3 hens in that coop for the first year and eventually expanded to 6.
We told all of the neighbors what we were doing before we did it because we wanted a chance to be able to address any concerns they had. They all, with one exception, absolutely hated the idea. Fortunately, we had the law on our side. We only let them know as a courtesy-we were in no way obligated to have their permission. Over the 2 years we had them before we moved, most of our neighbors came around to them because they weren't smelly-which was initially the main concern for most of them. That said, there was zero chance we could have hidden them-mostly because of the noise. A single hen can make a lot of noise. I went out to my coop about an hour ago to check on a broody hen and one of my polish was in the run and started screaming bloody murder when she saw me to let me know I better have treats. They're just....loud.
You likely won't live in that house forever. We wanted chickens in the first house we lived in but it wasn't realistic. Our second house wasn't ideal but that's where we started out. The third house was purchased with the intent of having all the damn animals we wanted with no restrictions and no close neighbors to deal with.
