Peru in general is getting expensive as there is a handful of good hotels and a lot of demand. For example, I did the inka trial back in 1998 for $80, now it costs $500. Entrance fees are also expensive for foreign tourists. It is possible and easy to backpack thru Peru for very cheap as there are hostels for about $5 per night, but these have shared bathrooms and no hot water. It is also possible to purchase a package once in Peru with a local agency, but this can be risky as scams and bad service are unfortunately common.
If you are looking for the a good deal on a package. Check the following link for information
www.peruforless.com
hope it helps