Stand next to a paint counter at any hardware store and people will come asking for "primer that can cover mold". Dark spots and bubbles are a sign of moisture and un-fixed it will continue to grow and cause more damage!! Covering up the spots is just hiding bigger problems.
Don't stick your head in the sand or just cover it up. If you are concerned call us asap. We can see behind walls and can check for moisture, mold and so on before knocking holes into your walls. We can test the air, take inferred images, and much more to find the root cause of your water issues. Call us today to talk through your concerns and steps needed to keep your home & health safe.