What is the difference? We are talking style here, and style is never compatible with non-professional or machine translations. If you intend to create a corporate image, sell a product or service or pass on a working philosophy, style is crucial and the translator must be aware of it. On the other hand, if you just need to understand a document, although accuracy is a must, style is not a big issue.

B.1 Machine translation
You can resort to machine translation to get the "gist" of an email or get a letter translated for a foreign pal. But be aware that it will do little for your business. You'll risk your image, your reputation and your future in the international market. A combination of both machine and human translation might be right, but few professional linguists will accept work editing a confusing translation.

B.2 Bilingual employees or friends
Turning to a bilingual friend is certainly a less expensive option, but being bilingual is not synonymous with being a translator. Translating has a lot to do with re-writing, so a good writer has a better chance of being a good translator than a bilingual speaker. Do you know many native speakers of your language who are brilliant writers?

B.3 Your own linguistic skills
You always address your foreign customers in their native language, talk business and negotiate in a second language. So you don't need professional assistance, do you? Perhaps not, but oral fluency is not the same as good writing skills. Your documents will be recognized as written by a foreigner. It's really hard to project the smoothness of a native speaker in writing.

B.4 Language School Departments and Translation students
Once again: skills necessary to perform a smooth translation are not those needed to teach, even if it's a foreign language. And, would you hire students to run your business?

B.5 Added value of translation agencies.
A translation company selects the most appropriate translators for each project, assigns a manager to your account, controls the quality of the job and provides you with consistent multilingual translation in different formats. This allows you to avoid hiring and combining several services. Recommended for big projects.