eBay users expect our platform to be truly global. Machine translation (MT) is needed to support and encourage cross-border trade. The implementation of MT has had a positive effect on trade. The MT content we are dealing with at eBay consists mainly of user-generated titles, descriptions and search queries, which pose specific challenges in the creation of quality corpora for MT engine training and requires multiple and refined quality assurance (QA) processes. After a brief introduction to MT in general, this case study will focus on post-editing practices and challenges in the creation of MT corpora based on our experience at eBay.