1999 clk rear window regulator faulty
 

I've posted recently about water entering the cabin, originally I thought from the driver's front window. Spent $200 labor to have door panel removed & glass adjusted, so says the invoice. When leak continued I brought the car back, and the dealer then said it was coming from clogged windshield/ac drain hoses. I brought the car in today along with the twisted & ripped seal between the front & rear drivers side windows. Today the dealer said the water leak was caused by a faulty driver's side rear window regulator, which causes the rear window to twist & not seal properly. The estimated repair cost is $1000 in labor because the entire rear paneling etc has to be removed. Naturally the car is out of warranty and I am only 5 months into a 24-month lease extension. Anybody have any thoughts? Will an oem car cover help?