In the end, it is determined by your journey itinerary as you'll be able to check out the jungle before or immediately after your tours in Cusco. From Lima to Iquitos you should have additional flights out there and doubtless also much less expensive kinds than from Cusco to Iquitos. https://kbookmarking.com/story16954217/the-2-minute-rule-for-peru-amazon-tours-from-cusco