Overboard (1987)

Joanna Stayton hires country carpenter Dean Proffitt to build a closet on her yacht. When they don't see eye-to-eye, he is left unpaid while she sets sail. The following day, she is fished out of the sea after falling overboard, suffering from amnesia. Dean sees a neat way to regain the money she owes him - he tells her that she's his wife; that way he gets a free housekeeper and mother for his four sons.