The Legend of Hell House (1973)

The owner of a haunted house employs a small group of people to spend five days living in it to see what they can prove about the afterlife.  There's a psychic, a physicist (and his wife), and a survivor of the last group that attempted to stay in the same house.

Nice creepy vibe with some genuinely scary moments. Alas, the expositional and almost silly end reveal nearly undoes the whole thing.

B-