In terms of the beginning investor, the mutual fund fees are actually an advantage relative to the commissions on stocks. The reason for this is that the fees are the same, regardless of the amount you invest. Therefore, as long as you meet the minimum requirement to open an account, you can invest as little as $50 or $100 per month in a mutual fund. The term for this is called dollar cost averaging (DCA), and it can be a great way to start investing.
What would make me sell: Sometimes there are good reasons to split up. For this part of your journal, compose an investing prenup that spells out what would drive you to sell the stock. We’re not talking about stock price movement, especially not short term, but fundamental changes to the business that affect its ability to grow over the long term. Some examples: The company loses a major customer, the CEO’s successor starts taking the business in a different direction, a major viable competitor emerges, or your investing thesis doesn’t pan out after a reasonable period of time.