Another alternative (along the same lines as the error trap used in col D in
the sample's set-up) with "Qty" input in E3 down and "Price" to be
calculated in F3 down ..

Put in F3, copy down: =IF(OR(D3="",E3=""),"",E3*D3)

Or, we could amend the 1st part of the formula in col D
to return zeros instead of blanks: ""
(the null string "" is what causes the downstream error #VALUE! in col F)

i.e. use in D3, copied down: =IF(OR(A3="",C3=""),0, ...
instead of: =IF(OR(A3="",C3=""),"", ...

Then to calc the price, just use in F3, copied down: =E3*D3

New lines w/o data will then simply show up as zeros in cols D & F

And if desired, for a cleaner look,
we could suppress the display of zeros in the sheet via clicking:
Tools Options View tab Uncheck "Zero values" OK
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Rgds
Max
xl 97
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Singapore, GMT+8
xdemechanik
http://savefile.com/projects/236895
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