It's based on the lives of the Warrens, who are real people, but the movies are mostly puff pieces that ignore that they're giant conartists (and Loraine Warren really wants you to know what a chad her husband was). The third movie is especially egregious in this regard because it completely glosses over how the Warrens screwed a man out of a sensible defense because they wanted another fiffteen minutes of fame.

My ex's mom had a picture with the real Annabel.