Barbara wields a silenced revolver in several scenes.A revolver cannot be silenced.
While Barbara is on the phone with Dr. Redmont she spots her victim getting into a Lincoln Town Car. As the car drives away Barbara makes it explode. When it explodes it is now a Mercury Marquis.
The evil woman tells the doctor at gunpoint that Tiffany can sit in as the anesthesiologist for surgery. That's ridiculous. It takes 12 to 15 years of medical school to become an anesthesiologist. You can't just point to any nurse in the room and tell them to administer anesthesia. The patient would die.
When Barbara blows up the Lincoln in an early scene, two different Lincoln's are used. A similar but battered white Lincoln is substituted in for the brand new one and blown up. The second Lincoln has rear fender skirts, yellowish stains (possibly explosive smeared all over it?) and a detonator cord attached to the right rear bumper
In the opening scene when the car explodes, the tow cable pulling it is quite obvious.
Near the end, when Julie's face bandages are removed, she reveals that she is wearing quite a bit of makeup, including heavy orange blush on her cheeks. Not only that: looking closely, Shelley Hack (Tiffany) and that actress playing Julie are obviously wearing the same exact makeup colors to a T.