Hiring a translator is not like hiring a plumber.
Unless you are fluent in Korean, or Mexican Spanish, you have no way of checking the quality of a translation that may well win you or lose you a client or important contract.
A translator whose profile you can take at face value is a rare finding. Beware of translators who claim to be able to tackle any subject; it is simply not possible to correctly translate a scientific text if you don't have a fairly good understanding of the terminology and processes involved.
A university degree is no guarantee either. Some aspects of translation can only be acquired after many years of reading and practice, and others, like a flair for words, cannot be taught at all.
Some agencies have in place a "four eyes" system for proofreading and quality control, but subcontracting projects to other agencies and translators often produces patchy results. Because the money paid by the client whittles down by up to 80%, the freelancers who work for these agencies are often unqualified and inexperienced.
One way to avoid these pitfalls when choosing a translator is to hire a couple of professionals to translate different parts of your text, and then have their translations quality checked by a third party. This is a cost-effective way to set up a long-term relationship with a translator whom you can trust.
These are a few points to look for in a profesional linguist:
• A passionate, creative, free thinking native language linguist with a flair for words.
• Self-motivation and eagerness to acquire new knowledge.
• A good understanding and in-depth knowledge of language/country-specific cultures.
• Researching legal, technical and scientific phraseology to find the correct translation.
• Following various translation-quality standards to ensure legal and ethical obligations to the customer.
• Producing final translated versions that are free of grammar, punctuation and spelling errors.
• Formatting of translated documents to mirror the original source material.
• Communicate with clients to suggest changes in the flow, style and smoothness of translated documents.
• Attention to detail combined with the ability to work quickly to meet deadlines.
• The ability to use initiative in a commercial context.