Trying to Multiply the result of an IF function combined with a VLOOKUP function

Hi,
I'm trying to multiply the result of an IF function combined with a VLOOKUP function by another cell that will change to work out commission rates. My formula is =IF(B9<='Commission Rates'!$A$3,"0",VLOOKUP(B9,'Commission Rates'!$A$2:$B$14,2)) located on cell C9. This formula is working fine and updates anytime I change the figures in B9. I am trying to multiply the answer to this which is a percentage linked to another worksheet by the variable amount in cell B9 and get that answer in cell D9. The only answer that I keep getting is "VALUE".
Please help I have no idea what is going wrong.

Thanks. Attached is my workbook

Sorry guys. Attached is unprotected workbook with all numbers reformatted and the #VALUE! error.To clarify I'm trying to multiply the monthly sales by the commission % so that when monthly sales change the commission payable should change as well

Thanks so much for this helpful info.
Your reply is to someone else's question from three years ago but reading through it today helped me immensely with my spreadsheet frustrations.
in my case I was trying to multiply the currency amount returned using a VLOOKUP by a number to get a unit price. But I kept on getting the #VALUE error message.
Despite checking the formatting of the cells I simply couldn't get the result of a VLOOKUP to perform a simple multiplication with another cell. Was pulling my hair out trying the cells formatted as Currency and Number back and forth. In the end after setting the formatting to number I just reentered the data and it worked as it should have.

Thanks Everyone. Appreciate the help. Works like a charm Tony.