Elvira uses her magic ring to cause a downpour, which douses the flames meant to burn her at the stake. Elvira and Bob should be soaked, but in the next shot when he unties her, they are completely dry.
Flipped shot: When her great uncle first appears in her house, the poodle growls and snarls. Originally, the poodle has a black fluffy left ear and an earring in the right. These switch over during the growl, and switch back again when the camera pans back.
When Vincent is chasing Elvira near the end of the movie, he has a bloody hole in his forehead from Elvira's stiletto heel as he slips through the cemetery gates, but she hasn't thrown it at him yet.
When Elvira first comes to Falwell, the hood on her car blows off, and lands upside down, but later, when the three young boys pick up the hood, it is right side up.
When Elvira encounters Vincent in the ally, her ring goes to his right hand, but when he comes out of the ally the ring is on his left hand.
(at around 78 mins) The police officer says, "By the power invested in me by the sovereign state of Massachusetts." It is actually "the Commonwealth of Massachusetts."
The comic book that Billy reads is "The Amazing Spider-Man" #299 (dated April 1988). At no point in the comic does anyone try to kill Spider-Man with plutonium, as Billy states. The plot actually involves Spider-Man tracking down a secret arms shipment.
Elvira's car's front tag says KICKASS and the back tag says 2MACABRE. While illegal in any state that requires both tags be displayed, this isn't a goof.
At the beginning of the Flashdance sequence, Elvira is wearing high heels, but during the dance, she's clad in flat shoes and standing on her toes.
The signage at the bowling alley spell the character's name as Patti. However, the end credits and closed-captions spell her name as Patty.
Chastity Pariah (Edie McClurg) is on the phone gossiping in her bathrobe and towel while Elvira is looking for a job. Moments later she is seen coming out of church all dressed up.
On her car ride to Massachusetts she gets to stop next to a carriage. During that short scene the shadow of the cameraman and his equipment on the floor is visible.
Elvira's signature Thigh high split dress shows she wears Pantyhose.
Yet on her first night in her inherited house, she gets undressed and is shown to be wearing suspenders, which would have been obvious with the split in her dress.