Question about how loud GGC can get.

I recently adopted a 6 month old Green Cheek Conure, he is totally adorable and sweet. My main concern with him is how loud he can get. He was silent the entire first day I had him except for when I went to put him to bed. He squawked and screamed for about 45 minutes. I know this is common, but I'm not sure if it was because it was his first night in a new home, or if he'll keep this up.

Anyway, my main concern is that I live in an apartment. Now, keep in mind that this is an old brick building, and the walls are pretty thick. The wall between me and my neighbor is concrete. My neighbors on the other side are seperated by 2 full staircases and 3 walls. Do you honestly think my neighbors will be able to hear him/have a problem with the noise? I love him and I hope this doesn't become a problem.

Our GCC is not loud at all. Does make noise but not loud enough to be heard outside the house

You could try asking your neighbors if it is bothering them.

Around here we have what I call the "noisy hour" for a while around waking and feeding time in the morning, and for a bit in the evening. The rest of the time, the noise is mostly contact calling, which is minimal and attempts to solicit attention, which I try to steadfastly ignore, and very occasional alarm calling (golden eagle in the back yard!).

Try to figure out why your bird is being noisy. I respond to contact calling with one or two answer backs, and I try to encourage calls that aren't screeching (wolf whistle, "hey bird!") If one or two answers doesn't reassure the flock that I'm around, I go about whatever I was doing and do not respond at all to any further calling (unless I recognize an alarm call, my GCCs is very distinctive). If you got to check on the bird, he may think "oh good, I've taught the human to come when I call!" and even if you come in angry and tell him to be quiet, he may still that! Any kind of drama can entertain a parrot and act as a reward, and IME GCC are especially responsive to that. Finally, make a point of giving him attention when he's quiet. Randomly go in to him and tell him all about what a good quiet birdie he is.

Scooter will sometimes do the squawking in protest at bedtime, but it lasts no more than five minutes at most. 45 seems excessive. Is the room dark? Do you use a cage cover? Does he get 10-12 hours of dark time? If you don't have a sleep tent or tube (I think the fleece covered tubes are probably the safest) he may appreciate one. My understanding is that GCC are full-time cavity dwellers -- they sleep in enclosed places even when not reproducing -- and mine sleeps on his back in his tent every night.