I assembled my first AR. Easy peasy.
You oughta try it. You can get everything in the mail except the lower receiver.
If you can change a tire, you can build an AR-15.
Now with all that new weaponry, where do we find ammunition and reloading supplies to fill the voids? I need some .280 rifle brass.
My tires don't come with tiny springs that fly at the speed of light, and hide better than cockroaches. It's best to build your AR with the assistance of several spotters/chasers, a magnet on a stick, a spare parts kit (several), and have the beer iced for afterward...
Eye protection and ear plugs (to protect the delicate ears of your spotters/chasers) are also a necessity.