Please assist with the given problem regarding working capital management.
Last year, Carl's Bail Bonds reported sales of $58,200 and costs of $22,700. The following information was also reported for the same period:
Beginning Accounts Receivable: $24,880
Ending Accounts Receivable: $21,520
Beginning Inventory: 4,270
Ending Inventory: 6,512
Beginning Accts Payable: 40,680
Ending Accts Payable: 44,540
Based on this information, what was Carl's change in net working capital for last year? What was the net cash flow?