Help Please! I'm not even sure if this is possible

Hey everyone, here's my problem:

I basically have a list of data coming from one source (directly from the customer), and a list of data coming from another source (contractor hired by the customer) on two separate sheets in a workbook. They are basically in the same format (same columns), but need to stay separate for data management purposes. From these two sheets the raw data go through to their respective "Data Cleanup" sheets. This is a cleanup step where I can substitute data for bad or missing data or note the data as duplicate so no further analysis need be performed. The data cleanup sheets refer directly to the original sheets, so same number of rows.

This is where it gets complicated - I want to pull the two sheets with the cleaned up data together on one sheet to do a calculation methodology analysis. Right now I have an if statement looking at the data from the contractor and returning the cleaned up data if the cell on the contractor's data cleanup worksheet <>"". If the cell is empty I have an offset function that allegedly should return the first cell of cleaned up data from the customers data cleanup worksheet. However, the offset only works for the amount of data we have now, I would like it to work whether we add or remove data from either worksheet. Here's the formula where it actually begins seeing "" cells and returning the customer's data, on row 949 of my method selection tab:

=IF('Contractor Data Cleanup'!A948<>"",'Contractor Data Cleanup'!A948,OFFSET('Non-Contractor Data Cleanup'!A$8,+ROWS('Non-Contractor Data Cleanup'!A948:'Non-Contractor Data Cleanup'!A$8)-ROWS('Non-Contractor Data Cleanup'!A948:'Non-Contractor Data Cleanup'!A8),0,1,1))

Obviously, where the formula begins on row 9 of this worksheet, 'Non-Contractor Data Cleanup'!A8 = 'Non-Contractor Data Cleanup'!#REF!.

I guess what I'm asking is - is there a smarter more transparent way to return data from two separate sheets in a workbook on one single worksheet?

Thanks!
Caroline

Nevermind, I figured it out myself. Instead of +ROWS('Non-Contractor Data Cleanup'!A948:'Non-Contractor Data Cleanup'!A$8)-ROWS('Non-Contractor Data Cleanup'!A948:'Non-Contractor Data Cleanup'!A8), I did +COUNTA(range)-COUNTA(range) and now it updates when the amount of data changes on the worksheets. Thanks anyways