ACCOUNT_FIRST_NAME ACCOUNT_LAST_NAME
ACCOUNT_ADDRESS_SINGLE_LINE
 
Dear TITLE LAST,
 Thank you for your letter of DATE returning the draft of the DOCUMENT we propose to send [to our customers].
  
 I am very grateful for the trouble you have taken to examine the draft and comment on it in such detail. Your suggestions will be very helpful.
  
 I realise the value of time to a busy person like you and this makes me all the more appreciative of the time you have so generously given.
  
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