Travellers that have enough time may consider another suggestion with British Airways (and their partner TAM Brazilian Airlines) to travel South America from Pacific to Atlantic side. Open jaw flights from Amsterdam to Peru with return from Uruguay to UK, Germany, Vienna, Prague or Paris are now availavle already for €438/£340! This is for a round trip flight including all taxes as well as checked luggage. 
British Airways promotional offer allows to book these open jaw tickets to South America in travel period till 30th of June 2016. (Based on date of your outbound flight to Peru). Valid for purchases made till 17th of April 2016 or until sold out.
Before you book.: Please note that althought flights with British Airways are routed via London you can not skip first leg of your outbound flight Amsterdam - London. Rest of your itinerary would be cancelled..
Booking sample
Travel date samples
11. - 27.5.
14.5. - 7.6.
18.5. - 12.6.
24.5. - 19.6.
8. - 22.6.
Another suggestions to Central or South America
To check your connection possibilities we recommend to use Skyscanner. This tool gives you quickly an idea which low-cost airlines are available from your home city. To book some afforeable accommodation in South America you may use Booking.com or consider following promo codes offered by Ebookers, Hotelopia or Venere.
Booking sample of cheap Flights to Peru with return from Uruguay from €438/£340 here. In this case you would be departing from Amsterdam to Lima on 11th of May 2016. You would be returning back from Montevideo, Uruguay, to London on 12th of June 2016.
