Reliable Sources
While you may not need a large volume of transcription right away, make sure the company with which you engage is capable of scaling if needed. They should have enough resources in-house to handle larger volumes when required, reducing the risk of low quality transcriptions at the same time.

You should also verify the specific skills of these team members as relate to English language skills, listening and typing skills, etc. This can be verified with credential requests as well as a sample project.

Project Management for Large Assignments
To avoid spending more time than you would like managing resources, ensure the team you hire has in-house project management. Clients should have a single point of contact instead of dealing with each transcriber on their project.

Quality and Accuracy
It is vital that your transcriptions are of the highest possible quality, fully proof-read and error-free before they reach you. To ensure this, ask for a sample so you can accurately gauge the quality before committing to a provider.

Competitive Pricing
Make sure you understand what the standard transcription rate is for your industry and compare prices for several different service providers. You can request quotes from vendors in advance, and should compare at least 2-3 different vendors to ensure you have a good sense of what it will cost. Make sure you find a good balance of quality and pricing, without any compromise to reduce costs.