one question about Unreal Engine 4

hello i have a question about unreal engine 4
can i buy and download unreal 4 and use it in 3 pc ??
can my friend use my engine ??
for use unreal engine 4 most i login in it ?? (like cryengine ) or no i can use it like udk ??
how price for buy unreal engine 4 ?? most i pay 19 $ in month or no ??

  1. If person who is using it will be just you it’s ok.
  2. No, he need own license.
  3. Yes, you need.
  4. You can just pay it one time and continue without updates. You are paying monthly for update, if you don’t need it or you want to update like after 6 months. You can cancel subscription and continue with using UE4. But If you release some commercial project you need to pay 5% royalty to Epic Games.