Multiplayer (Construction Simulator 2015)

Hello!
Going with a friend to play on multiplayer. Both have license. There are a couple of issues.
First - as actually happens multiplayer? Used tools and machinery the one who created the game? Or what?
Second - I've Got all of the additional content purchased, from a friend there, just few DLC. Will this be a hindrance? Or if you use the technique of creating, the others don't need to buy anything to use it?