=IF(AND($U4=DHARMA!G$4,$U40,$O4<"H"),$E4*DHARMA! $H$4+$F4*DHARMA!$I$4,"")&IF($P4<0,$P4*DHARMA!$H$4 +$Q4*DHARMA!$I$4,"")

After several rewrites, this function works and does not return an error
when the cells are blank, but now I can't format the cells that contain this
function. Strange.