Ok. I put extra parenthesis around and it worked. But then I realized I forgot the else in the first part and now it tells me the "," is incorrect.
IIf([status]= "Active" and [Type]= "Cost",([rate1]-[rate2]+[rate4],[rate1]),(IIf([status]="InActive",[rate1]+[rate3],[rate2]+[rate3])) AS newRate