A pharmacy delivering to regular customers, many of them elderly and many of them in buildings with no lift.
Everything goes in an insulated bag with a fresh cold pack, and the bags are swapped at every collection rather than reused through the day, because a bag with a spent pack in it is just a bag. These parcels are dispatched as direct runs instead of being grouped with other deliveries, which costs us efficiency and is the only way the timing means anything.
We set two rules with the pharmacy at the start. Only sealed items, and the pharmacy tells us on each parcel whether it needs to be cool or merely out of the sun. And where the item is temperature critical as a medical requirement rather than a preference, they do not send it with us at all, and we told them that rather than being asked.
The unexpected part of this account was the stairs. A significant number of their customers cannot come down, so riders go up, and that changed the time per delivery enough that we repriced it honestly rather than absorbing it and then rushing.
About twenty parcels a day for two years.