None of the murders occur as they did in real life. Stephen Parent was stabbed/shot, not bludgeoned. Frykowski does die on the porch, but not until after being tied up inside and eventually stabbed/shot. Sebring was not stabbed, but shot by Watson, and not while he was asleep on the couch. Abigail Folger was stabbed multiple times, but never bludgeoned.
At her party at El Coyote Restaurant, Abigail Folger mentions her birthday is in October. In reality, Abigail was born on August 11th 1943.
When the detective states "rash of home invasions lately"..the term was coined 20 years later as this takes place in 1969. He should have said " rash of burglaries lately" would have been more accurate.