That's good advice, especially if you see indications of a problem. A surveyor can tell you how serious it is. Even if you don't, it's a good idea to get a survey. It's not easy to tell how much water is in the deck by visual inspection. Some moisture is to be expected in nearly all boats. The issue is where and how much. A bit of moisture or rot around a couple of fittings is easy to repair yourself. More extensive moisture and/or dry rot is something for a professional.