Hi There
You helped me out with my query on NZ/Aus so I'll give you what little advice I can on Peru and bolivia. I did not not do any private flying but loads of commercial. Lanperu had nice jets but some of the other carriers fleets looked old and rusty!
Peru:
Must do the Inca trail - a 4 day hike near a city called Cuzco - which is 1 hour east from Lima by 737. Its very high up though so you'll need to take that into consideration for flying. Cant remember how high but I got a bit of altitude sickness - my 6 friends were all fine though. the trail is fantastic, 4 days 3nights camping and walking to the lost city of the incas. Alos we went to a place called Arequipa, 1 hour south of Cuzco - lovely city and close to the Colca Caynon - biggest canyon in the southern hemisphere and home to giant condors. Would be amazing from the air I'd say. However dont do the one way trip as the journey by land takes 6 hours - it was a nightmare. Do the 2 day trip.
Bolivia:
Preferred this to Peru, had only a few days there but was great. La Paz is cool - DEFINETELY do the mountain biking trip - a one day thing down the worlds most dangerous road, fast and risky. Irecommend using a company called gravity
www.gravitybolivia.com
Also, i'd check lake titicacca out, didnt have time myself but hear its worth going to.
Have a great trip
DQ