I am currently developing a helicopter and I am going to use the mouse.Hit's lookvector to point the helicopter in a certain direction.
If I set the helicopter's position through a local script accessing the mouse, will they helicopter only change position on the client? And If I make something transparent or opaque from a client/local script, does it only show up on the client's environment?
No, this is he only way to do it due to the fact Mouse is client-sided as long as the variable isn't a local part then everything should work. If this didnt't answer your question comment and i'll give another answer.