My 1999 cadillac seville sls has a leaking trunk, need to find a low cost repair?

I hear this is a common problem, check the rubber seal around the edge of the truck.

99sts same issue. I added a thin weather strip on hood, didn't work. I discovered water was from a gutter down spout a black tube in trunk passenger side behind shelf liner. That hose needs to be through metal/grommet and to drain outside. Solved water flood/leak.