Who Can Sign - For partnerships, only general partners can sign a contract, not a limited partner. For LLC's, a managing member or a hired manager can sign. For corporations, the company's president or chief executive officer is presumed to have the authority to sign. For an organization or association, a board president would have the authority, but may require a vote of the governing board to approve the deal.
Describe the payment terms for the transaction, including the total amount for the service, how much and when the deposit is due and how much and when the final payment is due. Spell out a time line or milestones. Include specific dates for the delivery of parts of the service or the final deadline for the service to be complete.