You are entitled to fully understand the proposed rates and retainer fee before you sign a retainer agreement, as in any other contract. This client Retainer Agreement is for ongoing service agreements between a client and consultant or contractor.Have you ever edited with an eye towards attorney fee deferral? If so, you may already know the language your retainer agreement should contain. This agreement for legal representation is between, AGENCY NAME, and CLIENT(S) NAME(S). Sample Retainer Agreement.