Nested IF statements not working

I have built the following formula that checks a checkbox and, if checked, checks another field to see if that is null. If the field is null, then it pulls a [negative] value from another field. If not null, then it pulls the value from the first field.

IF({Incl in Pipeline?}, IF({Net Cash Proceeds} = “”, -{Total Cash to Acq}, {Net Cash Proceeds}),“”).

All of the logic seems to be working except for when it’s supposed to pull the -{Total Cash to Acq} number. When the logic runs into this scenario, the formula returns a value of “0”. Any ideas?