Kaela Stevens is auditing Turbo Ltd, an existing client, for the year ended 30 June 2018. Turbo's accounts receivable was recorded at $4, 000, 000 and comprised more than 1000 customer accounts. However, Turbo's 10 largest customer balances comprised more than 25% of the recorded accounts receivable. As a result, Kaela is considering the use of dollar-unit sampling.

REQUIRED:
Outline four factors Kaela should consider in determining the sample size for accounts receivable, and indicate how she would determine the value to place on these factors.