It is in the actual Hamilton beach box, then an amazon box. It doesn't need any "building" only same assembling you'll do after washing it. I follow their advice and put a plastic bag in the pulp bin, and it saves having to wash that, limits the mess.
It is shipped in the actual juicer box inside a brown amazon shipping box. It is not "assembled" when it arrives, but that's because it comes in 6 parts that all snap together very easily and disassemble easy for cleaning. It's optimal that the juicer be able to be broken down in as many parts as possible because of how messy it can get. You don't want rotting vegetables left in crevices. So, no, it's not exactly assembled. But assembling it is just a matter of 1 minute. Hope this helps.
Yes. Everything is in the original box with factory wrap. It easy to put together. The brush is included. I just removed the items,washed them in water and snap/clip and started to juice. Hope this help.
Yes, mine came in an official Hamilton Beach box [just like the one at my local store] with owner's manual and there was the expected assembly... I put the blade in the plastic housing, attached it to the unit and put the pulp bin in place as explained in the manual. Before trying the juicer, I searched YouTube and found a video specific to the Hamilton Beach juicer that was very helpful.