roof that comes to the door with the goal of selling me a roof. Some of these guys will actually cause the damage and then show you pictures of the damage when they climb down, or show you pictures of a different roof. They know the majority of homeowners won't get on the roof and look for themselves.

Unless the damage is extensive, I'd look into repair rather than replace. How old is the roof that's on there now?

There shouldn't be "soft black spots", I'm not even clear on what that means.

If you have a composition shingle roof, the actual water barrier is the felt paper under the shingles and over the plywood. The shingles are there to protect the felt paper from breaking down when exposed to the elements. If there aren't holes in the paper, then repair.