just an idea

can a "next available" box be added to order form this being recomended to 2x travel and be admin adjustable. ill explain by example

if i send a bus to liverpool from cumnock the travel time is arround 4-1/2 hours but the vehicle is not available for hire again until it is back at base (not including legal drivers breaks) thus the period of unavailability is 9 hours plus in the diary.

Hi a1lux,
you can actually tackle availability issue by using Base settings:
Dashboard > Settings > Base settings > Base latitude and longitude > Base to Pick up/Drop off calculation: Yes
If you keep Value at 0 then no additional cost will be added to Total.
You can also use this feature for Fixed routes by adding Time and Price calculation or just Time calculation.

In your case just Drop off to Base calculation should be sufficient to block off availability of the car.
To cover Driver's legal brakes you can also Add time after each booking (minutes).

Hope this helps.
Kind regards.

SORTED THANKS