I remember the cover was white with a monochromatic pencil-style drawing of a rundown old house with a bit of grass/ground in the foreground.
A lonely, rejected boy named Toby is forced into this spooky house by bullies, I believe near Halloween. The boy is 12? Possibly younger? I’m sure his name is Toby, and that is likely the name of the book, but I can’t find it by that title anywhere.
He has to spend the night in this old house because the bullies block/locked the doors. I believe he was locked in the attic? Or stayed there overnight. He learned that his fears are in his head and he needn’t fear his imagination.
I read it before 1980, so it would be at least that old, but not much older.
It isn’t long, or large. It might even be a short story, but I’ve not been able to find one by that title that fits the story either.
The cover reminded me of Where the Sidewalk Ends in style of drawing.