Write a letter regarding hiring an Advertising Agency.

Dear Sir, 

This is to inform you that we are pleased with your presentation as on [DATE, ex. Tuesday], regarding your proposal to handle our accounts. We would further like to inform you that we have since decided to procure your services for our firm [FIRM NAME, ex. ABC Co]. 

Kindly contact us at (phone no.) so that we may arrange a time for reviewing and signing a contract. 

Sincerely,