You should handle any water problems before your agent begins to market your home. If you have any moisture problems, honesty is the only policy. Be ready to provide a receipt from a reliable waterproofing company showing what caused the leakage and what was done to correct the situation. If the dampness is caused by clogged gutters or misdirected downspouts, it may be corrected by building up the soil around the base of the house. Your Realtor may be able to provide you with a list of companies that specialize moisture treatment.