A huge bill prompts Mike to install a payphone to teach the kids a lesson, but his plan nearly backfires when he is forced to use the payphone to close a business deal.
With Carol and the three girls added to the household, Carol convinces Mike to install a second telephone line into the home. One line into the den would be for Mike and Carol's exclusive use (and the kids only in emergencies), and the kids and Alice would use the telephone in the family room. The second telephone line makes matters worse as the kids constantly use the den telephone on what they deem emergencies, while someone else in the house is using the family room telephone. So Mike decides to restrict the kids to the family room phone.
However, since it only makes matters worse for the kids constantly squabbling for phone, Mike and Carol try to limit their calls (such as hour-glass and egg-timer), which don't help either. The last straw for Mike is when he receives the astronomical telephone bill, and sees all the toll charges incurred. After Alice visits her boyfriend Sam the Butcher, who had recently got a payphone due to losing his profits on his customers asking to make phone calls, it gives her a perfect idea, and she tells it to Mike. Mike thinks he has the answer: exchange the family room telephone for a pay telephone. Although the extra money provided to each child to make telephone calls is more than their telephone bill, Mike believes it will teach the kids financial responsibility. Sure enough, the kids are even hanging on more to their money. But Mike doesn't foresee a certain business problem the pay telephone causes him.