Boogeyman 2 (1983)

I've never seen Boogeyman, but apparently much of the footage from this film is from the first one. Lacey returns to her childhood home where she and her brother were regularly beaten by their mothers boyfriend.  While there, she accidentally breaks a mirror.  She brings the shards home, but there is one piece missing.  In a fit, she throws the mirror into the sink and it bursts into flames.

Lacey's friends want to make her story into a movie, and throw a party where they try to exploit her tragic past.  One of her friends husbands, Mickey, doesn't want to have anything to do with the film as he doesn't think they should exploit her.  Everyone else is fine with using her.

The killings are done by a big white hand holding a small piece of the mirror, which apparently can control inanimate objects as we have death by electric toothbrush, shaving cream, garden hose, exhaust pipe, corkscrew, BBQ tongs, a slamming window, and an exploding car.