You write an inquiry letter to acquire information. Explain who you are and why you are writing. Make your questions precise and clear, and therefore easy to answer. Explain what you plan to do with the information and how you can compensate the reader for answering your questions.

This writer’s task is to motivate the reader to provide some information. That information is not likely to lead to a sale because the writer is a graduate student doing research, not a potential customer.

Notice the flattery in the first sentence.

The writer presents specific questions in a list format, making the questions easy to read and understand.

In the final paragraph, the writer politely indicates his schedule and requests the reader's response. Note that he offers to send the reader a copy of his report.

If the reader provides information, the writer should send a thank-you letter.