I worked in the industrial camp /mobile home industry for a couple of years doing warranty work and maintenance . I have no faith in that grey butyl tape what so ever. It's cheap, easy, and quick to use when assembling . A simple check is to remove the vinyl cover on the corner molding and look for rusty screwheads. If you find one, remove the screw, you'll need a 1/4" nutdriver bit for your drill. If the shank is rusty, you know you have a leak. If you and your wife work at, it should only take a couple of weekends to change over to Profex or Siskaflex. You should be good for at least 20 years. Instead of 20 months.