When selecting your Pickup (start) and Return (end) date and time, the app will automatically calculate the cost of your trip for that period. This can be seen below, $15 for 1x hourly tariff. To understand how this is calculated, click on the quoted price.

Here you will see the full details of the tariffs. The minimum tariff for this particular service is one hour, charged at $15. So even if you had only used the vehicle for 35 mins, it would still cost a minimum of $15.