We also just finished this. He confessed to 30ish murders. There could be more we don't know about, he was murdering at a rate of one a month at one point and he was active for at least 10 years. That is based on the first confirmed victim when he was 27 yo, Bundy at 14yo was a paperboy, a girl also 14 disappeared from her bed on his route, no one was ever caught (that does not happen very often).... When you also factor in he was caught by luck on two occasions and there was only one incident where his attempt to abduct and murder failed.
So without those two occasions where he was stopped by police how many could he have got away with?