The itinerary lasts 14hrs 43min, and has 2 steps, and it will cost 30 euros minimum.

Paris - Nice
The step from Paris to Nice lasts 12hrs 43min. You'll travel in a night train.
You can find tickets from 30 euros.

Nice - Valberg
The step from Nice to Valberg lasts 2hrs 00min. You'll travel in a day bus.