i charge my fee right up to the time they leave and I close the door, as per my contract. my fee is $1.00/min (by my clock) for the first 30 min, after 30 min its $2.00/min.

ex: 30 min = $30
32 min = $34 ($30 for first 30min and $4 for the extra 2 min)

You want to cut into my family time, you will pay for our time.