The following commentary comes from an independent investor or market observer as part of TheStreet's guest contributor program, which is separate from the company's news coverage.NEW YORK ( InvestorPlace) -- Small-cap companies can be some of the most innovative and profitable on the market and can bag you big gains. But if you pick the wrong ones and end up with an earnings dud, you can do some serious damage to your portfolio. Today, I have 10 small-cap stocks for you that you should sell ahead of the companies' earnings announcements this week. These companies are finding it hard to make a profit and are only marginally growing sales or seeing business go to other competitors. This is not the type of movement I like to see in my stocks and whenever a company with these fundamentals pops up on my screen, I immediately send it to the trash.