I just bought a used 2015 Model S 85 "no roof" and it has this very leak. What did it end up costing to repair? I don't have a warranty so I'm looking at a ball-park to plan for when it goes into service in two weeks. It rained on the day I bought it, and by the time I noticed the stain it was already dry, so I wasn't sure if it was an old repaired leak stain that I just hadn't seen, or a new leak. I poured pitchers of water all over the roof and no leak, so I took it through a cheap basic car wash to see if it leaked again and it did per the other picture. So my guess is it's coming in somewhere near the front and channeling down to the back light? Anyway, any information you could all give would be great, in case it's something I can repair myself.