If you don't need the money, wait to sell your bitcoins. Its possible that next year prices of bitcoin were bigger than now. (But it isn't 100% secure).
yes because we can hardly predict the movement of Bitcoin,Bitcoin prices can sometimes be very high and could be the price of Bitcoin down.
I think waiting for the right time is a great way to sell your Bitcoin,keep Bitcoin in the long run,if you have found a high Bitcoin selling price then sell it at that time.