I am working on an invoice that is using VLOOKUP

I have surpressed viewing the #N/A with conditional formatting. However, I
would like to have a sum of the columns that I have used this conditional
formatting with.

I originally did not use conditional formatting. I was trying to create an
"ISBLANK" formula which I could not get to work.

I know how to surpress the #N/As in printing only but I am doing this for
someone who is quite illiterate and they want to view the invoice "cleanly"

Any suggestions would be appreciated. Thanks. Happy New Year.