I am taking my 2001 in tomorrow for the same thing. It started off with the smell from the vents. Now, it is dripping from someplace all day long. I tried looking tonight, but I can't find it. It looks like it is dripping from three spots. The other thing that started yesterday was steam from the vents.

I got a quote of 800-900 at the dealer for the heater core, and 600 at a private shop. It goes to the shop in the morning.