How to ship personal items to the USA?

by Frank Cerra
(Cliza, Bolivia)

My wife and I have lived in Bolivia since 2014 and love it. However, due to the need for medical treatment in the USA, we need to return permanently. We need help for shipping our books, some clothes, and personal items back to the US. Aside from FedEx, DHL and UPS, how can we ship back as cheaply and safely as possible? We will not use Movibox. We would be grateful for any advice from ones with experience or knowledge.