Help with complex if statement formula

Hi All,

Good morning. I am trying to come up with an IF function formula or some other better formula to do the below in one column so i can copy down;

If cell G2=K, then H2
If cell G2=S, then I2
But if cell H2=0 or blank and I2=0 or blank, then J2*K2
and if K2 is blank or =0 then J2*L2

I have attached an example work sheet (Book1 - if func help).

Thank you for your assistance.

Pi