K.D.
I agree that if she is asking to shave her legs, then it is time. I, personally, would not recommend a hair remover because of all the toxins you absorb and breath in. They smell so strong and that can't be good.
I recommend an electric shaver. That's what my daughter started with and what I started with too. But if she really wants to start with a razor, get some disposables to start with that are designed for women and to get a smooth shave. I always shave in the shower, last thing I do. That way the hair on my legs is all wet and easy to shave.