We all have seen software programs that are able to do translations. But if you read the documents translated with them carefully, you will understand that they are not able to produce grammatically correct documents. They are only able to provide the meaning of the original document in another language. Therefore, if anyone believes that a software program could do the translation of business documents, he is misinformed.
If you read computer generated translations, you will find that they have serious readability issues. They could not come anywhere near jobs done by translation services. Therefore, it is a misconception to think that you could buy a software program and translate your business letters.
There are many online companies that advertise this type of programs but no one guarantees that they are able to translate business letters to have translations of the expected quality. Therefore, believe in the provider of your translation jobs that does it manually.