Custom Peru Travel Itineraries
... are a great way to see what you want to see of Peru, but sometimes can be more expensive than what you had thought.
Best if you join a standard escorted tour, offered by tour operators, and ask them to customize the ends of the tour.
A good tour operator will know Peru well and might be offering exciting places you have never heard of, and therefore had not thought about. It might be worth to look through their itineraries carefully or just ask them which of their standard tours would fit your tastes best: culture, architecture, agriculture, beach, fauna, flora, etc.
If that fails, and you have sufficient money to explore Peru on your own, purchase a good book on the country, such as The Rough Guide to Peru.