The donor acknowledgement letter would be the top half of the page, and the tax receipt on the bottom half, so the donor is only receiving one document. This will automatically mark the gift as "acknowledged", automatically generate a receipt number, and automatically mark the gift as "receipted". There can be different versions based on what's needed, and one would use a query to pull up the appropriate constituents/gifts. This option is available in eTapestry, and it saves a lot of time. It also makes things easier for the donor to only receive one document, and improves the stewardship of the non-profit.