Calculation based on combining duplicate data

[crazybake]

My scheduling application is based on several pieces of equipment and the jobs which are assigned to them. A user can click on a day and see the jobs and hours associated with that piece of equipment... here's the dilemna.

Jobs which are alike (i.e. same colors in the job) only require the machine to setup once and all of the like jobs can be completed. However, some days there are many unlike jobs (i.e. some have like colors, others do not) and require the equipment to setup several times at 6 minutes per color change.

Because the schedule changes so much, can someone suggest a way for a script to set color criteria for job 1 and base al of the other jobs upon it. If colors match, no setup", if not add 6 minuted to each job where a color doesn't match?

thanks