Reader says... I have $100K invested in XXX. As the stock price has plunged, I am wondering if I should buy more, hold or sell? Should I buy more or should I invest in another stock? AK says... Remember the importance of position sizing. If your investment makes you worried, it might be because it is too big. Don't bite off more than you can chew. 1. Always ask why did you invest and if it still makes sense now? 2. Ask if you did not invest back then, would you invest now? Then, you will know what to do. No matter how attractive an investment looks, it is rarely a good idea to throw in everything including the kitchen sink. What? You don't know how to tell if you have thrown in the kitchen sink as well? ......