User fields allow you to record additional data of your own choice in a more structured way that just adding plain text, however you cannot search on them (unless you're using the customer contact screen).  This is where Flex Fields come in.

Currently there are three Flex Fields in Onyx and they are all used in the vehicle screen, they are for dates and can be used in a similar way to MOT and Service due dates in that you can use them to trigger reminder letters.  So for example, if you maintain a fleet of taxis you may want to send a letter to each taxi driver when their taxi test is due, for this you will rename one of the Flex Fields to ‘Taxi Text’ and then use this to record when the taxi test is due.

To enable and name Flex Fields go to the main menu and select Maintenance -> Options and then turn to the Flex Fields tab:

Enter (in this case) ‘Taxi Test’ in the Flex Date 1 field and then close the screen.  Now when we go into a vehicle record we will have an additional field:

We can create letters based on this field in the same way that we create MOT reminder letters:

We set the text used in this letter by: