If your % Due field looks up 100%, then it would appear that your Fees Due field could look up the flat fee ( which is currently £200)
Then you just need to display the text "fixed" at the correct time.
Option 1: Type "Fixed" on your layout as layout text. Use conditional formatting to make "Fixed" invisible except when the role is one of the two values for fixed dues. Do the same for the % Due field using conditional formatting to make it invisible when "Fixed" is visible. To make the text invisible set the font size to a very large font size (for layout text or field in a single row and font size 10 or 12, changing the font size to 120+ usually makes the text/data invisible.
Option 2: define an additional calculation field that returns either "FIxed" or the contents of % Due depending on the value of Role (use a case function) and put it on your layout in place of the % Due field.
I think the conditional suggestion may solve the first part, need to try it out will also look at the calculation aspect too.
Many thanks for your help
Done what you suggested and worked a treat, one query I'm using repetitions and if I change things in the other repetitions it only changes the first one, is there a way of specifying linking to the relevant line?
To repeat an answer posted to another thread, that is probably by you to ask this same question. That's a built in limitation of repeating fields. The solution is not to use them. Use a table of related records, one record in place of each repetition to store the same data. Then you will not have an issue with looking up data from a related table as now you are not using a repeating field.
Note that repeating fields were once the only way of entering multiple items associated with the same record. But the release of FileMaker 3 made using related tables possible and the use of repeating fields has been the less than best way to record such data ever since that version release.
Actually one was a look up question and one was a calculation question so if they are the same then I stand corrected.
Yet since you need to move to using a related table of records, this question is no longer an issue.
Will this work in a portal? I still need it to display 'Fixed' when a certain role is selected. Basically I'm trying to create a purchase order template.