You either buy them from the TF2 catalog or you get them in random drops. So far there haven't been any way to get them for free, aside from trading and finding them.
You can't but it would be cool if you could
No. You can only gift the items themselves.
The "richest" player in TF2 is Bobsplosion: backpack.tf/profiles/76561198027097747?time=1462147200 However, as of May 1, he has moved all of his items to a private account so that he wouldn't be bothered.
No, they will not. Only in the event of out-game idling would they do that.
no, the items were only available for pre-release of AC:R. You can craft the items in game. Blueprints can be found on the tf2 wiki
Yes. TF2 is a GREAT game, and I recommend you "buy" it. TF2 is now free to Play.
There is currently a total of 235 hats (excluding the 124 Miscellaneous items) in TF2.
No, TF2 is not playable on a phone
TF2 is free-to-play
No you cannot trade weapons for beta tf2 to normal tf2. Beta Tf2 is considered to be a completely different game by steam. Therefore the two game's inventories are not compatible.
Nothing happens, that information is saved to the steam servers. In other words they'll be there when you re-install
You can either delete items, craft weapons together, or buy a backpack expander/ get premium