I am setting up a model and in doing so I want to setup a dynamic lookup
command to streamline my work. My model consists of 3 separate workbooks.
Two of the workbooks serve as lookup tables (one for enrollment, and one for
residential development) to the the third workbook. Miguel helped me earlier
with a command for my residential lookup.

the command works fine and appears as:

{=INDEX('[res_development.xls]Saz
Summary'!$D$6:$D$711,MATCH(1,--('[res_development.xls]Saz
Summary'!$B$6:$B$711=1110823)*--('[res_development.xls]Saz
Summary'!$C$6:$C$711="SFD"),0))}

my enrollment command also works and looks like:

=LOOKUP("1110823",'[geo_stud_0607.xls]lookup
table'!$A$2:$A$361,'[geo_stud_0607.xls]lookup table'!$B$2:$B$361)

What I want to do is streamline the model and where it says "1110823" in my
formulas, I would instead like for it to reference cell I3. This way, when
I copy and paste my work sheets I can just change cell I3 and the sheet can
update with the proper information from the other workbooks. I attempted
this with my array formula and it worked for the first one, but once I copied
and pasted the page and attempted a new number it updated the corresponding
cells with "N/A". I also tried to use a VLOOKUP for my enrollment but it
also came back with an error.

the VLOOKUP appeared as so:

=VLOOKUP(I3,'[geo_stud_0607.xls]lookup table'!$A$2:$B$361,2,FALSE)

I can explain more thoroughly if need be. I'm a little new to these more
encompassing formulas and have been finding them a little tricky. I just
want to make my sheets more dynamic and whanted to know if this is possible.
Thank you all for your time.