This seems very unwise and unnecessary.
Typically product data contains a single record for each product, with its various characteristics (ID; price; etc)
Why would you want your product data to change because you once ( or twice; or whatever) included this product in an estimate?
I don't want to have to enter products into my catalog. To save time, I want the items to be entered in on estimates and automatically copied across to product catalog. Then, in the future, the items that have previously been entered will pop up in my "Estimate Data" table - referencing my "Product Data" table.
You know how to do that?
A checkbox field (customvaluelist:1) and a new relationship (based on this checkbox value) with estimates and products could show the records in products table. Then you may write a script to export anywhere.