SUM(AND(ISBLANK formula question

This is my first post on this forum, though I have been using it for years. I appreciate all the brilliant answers that have helped me.

I am having an issue with the ISBLANK function. We have a guest list that took on a mind of it's own after guest numbers on different forms were modified depending on which executives were requesting extra guests, and I am trying to get a more accurate guest count. I am trying to return the value "2" if the 2 [extra guests] columns are blank and two other columns are marked "yes". If either of the [extra guests] columns have a value, then it should return the value "1". From there, I add that number (either 1 or 2, depending on the criteria) together, so I can get a total guest count. I tried to start simple and add in one ISBLANK function into my formula that was already working (except for the issue of adding another guest if the [extra guests] columns were not blank, which I didn't want). But I can't even seem to add in one ISBLANK condition without me getting an error. This is what I am aiming for:

=SUM(IF(AND(ISBLANK([Extra Guests]@row), ISBLANK([Sterling Extra Guest Numbers]@row, [Attending?]@row = "Yes", [Guest?]@row = "Yes", 2)), IF(AND([Attending?]@row = "Yes", [Guest?]@row = "No"), 1, 0)) + [Extra Guest Numbers]@row + [Sterling Extra Guest Numbers]@row)

This is what was working:

=SUM(IF(AND([Attending?]@row = "Yes", [Guest?]@row = "Yes"), 2, IF(AND([Attending?]@row = "Yes", [Guest?]@row = "No"), 1, 0)) + [Extra Guest Numbers]@row + [Sterling Extra Guest Numbers]@row)

Any help would be greatly appreciated. Thanks!!!


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