thanking a rep

How do I write in Spanish "Thanking a rep". Thanks for your help and advice.

Please, give us context. Where did you read that expression?

I am writing to thank a book rep for visiting today.

Hello, Jan.
"Gracias por tu/su ayuda y asesoramiento" podría ser una forma de ponerlo.

Hello janinthesun.
The title of your thread should include the phrase you want to translate.
If you want to know how to say 'Thanking a rep', then 'Dando gracias a un comercial' would be one translation.
If you want to know how to thank a rep, you should tell us exactly what you want to say. The sentence given above by Amapolas is probably correct but you haven't given us the original sentence in English.
Please take a moment to read the 'quick guide to the Spanish-English forum' and note what it has to say about how to ask a question:

In the first post, include 3 key elements of context:
a. Ask a specific, clear question.
b. Show us a complete sample sentence in which the word/phrase was used.
c. Describe the situation and the dialect of the speaker/writer.

Thanks
Bevj
Moderator