Thanks for the advice, I frequently use that method. It is not an option to stop buying bitcoin even if the price is high or even if the price is low. The same way to selling, it is not the price that could dictate when you should buy or when you should stop. Because no one knows when is the right time when those price reached. When I trade, the profit is much the priority than the actual price of bitcoin. One can gain even the price is so low. Sometime when you set a certain price and the price didn't reach, suddenly, the price drops and you have lost your chance to sell in a much higher price.