Our Hilleberg Keron IV tent is about 20 years old and used quite often during that long time. Globetrotter Ausrüstung, a German retailer for outdoor equipment with several stores and an online shop, offers to check tents wether they are waterproof. We sent them the tent and got it back with the note that everything is OK and there was no need to repair anything. Of course we had to pay a fee for this service, but we think, that Globetrotter acts very fair not forcing us to have anything being done on a product that may be outdated but is still in good shape. Have you ever tried this with your local garage?