tezer86,
Typically what I do for this kind of stuff is on your target object make 2 states each with a global event attached to it. As an example call the events "Set Target" and the other "Set Target RPC"
Set Target should locally set the turret target for your own client but the trick is to include an RPC call (Set Target RPC) in the event that targets "self" and sends it to "others".
The only difference between the two states is that the local one includes an RPC call, the RPC state does not (if it did you would have an endless loop of RPC calls being sent out), otherwise they should include exactly the same actions.
So "Set Target" would be triggered locally with "Send Event", it sets the target locally and also fires off the RPC event "Set Target RPC" to "self" for "other" clients.
This is basically what I mean, below I'm using one state to trigger an RPC call. This way I can tell a game object to locally create some particles instead of needlessly instantiating them across the network. Then the particles themselves monitor when they are no longer needed and self destruct.
In a 4 player game I'm easily pin-pointing who is poisoned and what should be done about it.