When Brewster calls Fairfax to tell him that Walker is in his office and demanding his $93K, the voice of Fairfax is definitely not the voice of Yost/Fairfax.
I'd ask why but not much in this film made logical sense (which made it all the more enjoyable).
I am wondering what that character actually was. I didn't recognize that voice either, but Lee sort of did, although his face was wooden.
There is one set of scenes that made me unsettled and that was right after Walker's wife killed herself.
All of a sudden, she's gone, but Farifax is there outside, then there is no furniture...the door is boarded over...was his wife really that sick that she killed herself when he showed up...what is the purpose of all that.
Where did Angie Dickinson get that dress at the end of the flick, after she and Lee hooked up?
While watching this scene(Brewster's speaker phone call to Fairfax) tonight during "Point Blank", it sounded like James B. Sikking (the hit man) on the phone. That might make sense since he later killed Brewster for Yost/Fairfax. Only plot hole would be why Brewster (Carroll O'Connor) didn't notice the difference in the voice.