Purchaser availability for optimal routeplanning.
Upgrade "Purchaser" to mark 3-4 timeblock / day suitable for visits. Use that info when planning a visit. I.E. "only 2 of 3 of you purchasers are availabel that time you plan your visit. Is that ok? Yes/no. Etc. Effect: Better planning and visit performance!

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Stephan Johannes commented
I asked whether it is possible to plan several contact persons on different days and your question Björn, whether it is possible to plan days on which most of the contact persons are in the store. That is the answer:
"This is not a problem. In both cases, the customer would be created or transferred several times in portatour®. Each contact person then has their own visiting times. If these times overlap on individual days, portatour® will automatically suggest these contact persons together on the optimal day."
So both are possible!