Comparing two data sets: formula? ... or do I need a macro?

Hi everyone,

I am in the process of comparing similar data from two different sources (ergo they are not formatted exactly the same). Please see attached sample document. Customer name from "data source #1" does not always match 1 to 1 customer name from "data source #2". As you can see on "data source #2", I'm currently showing the following formula in column B: =VLOOKUP(A3,'Data source 1'!$A:$B,2,FALSE). Obviously a VLOOKUP formula is not the way to go due to the fact that over half the results need manual checking.

I thought about doing text to columns on "data source #1" to remove the embedded customer number from the name; however this creates the reverse problem because some of the customer names on "data source #2" DO contain customer number (and need to continue to do so).

Any ideas for me before I start manually comparing? As you can see, I've sent 30 samples from the letter "A" so there may be a lot to check. Would prefer to use a formula to accomplish end goal, but not opposed to writing a macro to accomplish.

Ultimate goal here is this: if customer exists on "data source #1" and "data source #2" want to populate a 1 in column B on "data source #2"; if customer exists on "data source #2" and does NOT exist on "data source #1" want to populate nothing (i.e. blank cell) in column B on "data source #2".

Also, if there is a way to somehow "list" those that exist on "data source #1", but do not on "data source #2", that would be helpful. Though I suppose I can do the reverse of whatever solution I come up with for the "data source #2" tab above.

Thanks in advance - appreciate always learning