Possible Clues:

• Original model
• The first to be a paid secretary
• First working version
• First full-scale working model
• Pretty poor arrangement, not right, for the first of its kind
• Just an example of one who is not an honorary secretary
• The model is paid to operate the keyboard
• A model of one paid to deal with your correspondence
• Original model - top poetry (anag)
• The first sort of professional secretary, perhaps