What to expect
Five nights, three places to sleep. That gives this outline enough variety. Moquegua gets the museum day, Ilo the coastal pause and Tacna a day for history or rock art. The best part need not be the same in each town.
How it fits into a journey
Day 1: arrive in Moquegua. Day 2: town and Museo Contisuyo. Day 3: travel to Ilo and stay by the coast. Day 4: travel to Tacna. Day 5: Miculla or Campo de la Alianza, plus town time. Day 6: departure. Set arrival times through actual transport choices.