Vba Macro vlookup issue

So what I would like to accomplish is if there is a number in cell c i looks at the lists page cell A and cell B to see if there is a yes in the B cell next to the value in A cell if this is true then it adds C3*1*ws+c3, this works correctly but if there is a blank in cell B it should just return the value in cell C3, but all i get is false in the cell. How can i get this to work correctly?

=IF(ISNUMBER(C3),IF(ISERROR(VLOOKUP(F3,Lists!A:B,2,False),c3)),IF(ISNUMBER(C3),IF(VLOOKUP(F3,Lists!A:B,2,FALSE)="yes",C3*1*W3+C3)))

I was not sure what to title it exactly, I apologize if its bothersum. The vlookup(F3,Lists!A:B,2,False),c3)) is what I think the issue is.

Sorry for the late response I do have one here thank you so much for taking the time to help.

Thanks so much davesexcel, That worked great

One last question, how would you get the round up function to work in cell L so it rounds to the nearest whole number?

=IF(VLOOKUP(F3,Lists!A:B,2,FALSE)="yes",C3*1*X3+C3,C3), Thats the Formula thats in cell "L" right now