Hello Lindsay,
If you set up the Time Slots globally, then it would no longer be possible for your clients to select an exact and custom duration of rent through the date-time pickers for pick up and drop off.
The Time Slots serve as a way to offer fixed rentals duration/options, and if you enable them, clients will only be asked to select a date for pick up and a duration from the apposite drop down menu listing all of your Time Slots. This way, the selected Time Slot will return the total duration of the rent as well as the start and end dates for the rental order.
If you would like your clients to be able to select one or two hours, then you should either add more Time Slots of that duration, or you should not use them at all, so that anyone will be able to choose the exact duration of their rent.
We hope this helps!
The VikWP Team
