Modeling + Making cars move in gmod help needed

I have a few questions, I will look at other vehicle lua’s and try to figure it out from there, but I have a few questions before I start on this.

Modeling: Any limits to how much of anything I can use? Size of car? I am sure there’s a limit to something, I forgot the name to that thing. I think it’s called Faces.

Textures: Any limits? Pixels?

Animations: Do I need to name a animation a certain name or what not? For the driving wheel/wheels.

Lua: Any notes or important stuff that I should know?