It's no 30min. Assembly, unless you have a 6x6 Post, already in the ground.
I had a 4x4 that my old mail box was attached to and there first plastic post that slides down over my existing post made look like a tooth pick. Terrible design.  Yea looks nice in the pic.
So I will get 7 or 8in. Bolt drill a hole in the bottom of there white plastic post and make it work. Not putting in a bigger post. So think twice before buy this mailbox.