The right time is when you have the guts to gamble and invest your money to bitcoin. Basing your decision to the price of bitcoin will bring you nowhere. No one could tell when would it hit the bottom, though it is great factor, if you don't have the courage nothing will happen to you. Comments and opinions here are just suggestions to support your decision, you always have your own will to decide what you are going to do. Try to depend on yourself and see what you can do .