Consider arranging a location where users in your area can bring their computers for PC Access installation and testing. The user need only bring his/her system unit, keyboard, mouse, and (optionally) their printer, as the installation site can supply a monitor with standard VGA connector.
MFM has resorted to having several users bring their computers in for us to examine, after failing to fix their problems over the phone. In most cases we were able to fix the problems once we could see what was going on. Also, some users turn out to have major hardware or system software configuration problems, and these sometimes require opening up the computer's case and re-jumpering expansion cards.