How are the cullens so rich ????

I mean when anda read the story anda obviously know that the cullens are sooooooo rich
but how is that so if they all have the newest and fastest cars and they spend so much of it on everythig and carlisle is the only one works in the whole family and I dont think he takes that high salary in that small hospital in forks......


tHaNx VeRy MuCh