Altiplano :)
the Republic of Chile and Brazil (the South American country)
The price would vary from whom you travel with (southwest, delta, etc), and how many people you are traveling with. Some companies may give discounts..
Peru landmass is 1,285,220 square kilometres.Bolivia landmass is 1,109,580 square kilometres.
Bolivia border with Peru to the southeast with the departament of Puno in Peru join the titicaca lake,