If you have Estimates in your QuickBooks company and you are converting to Sage 50 Premium Accounting or lower, you will see this window. When you convert, your Estimates will become Quotes. For these quotes, you need to specify a good-through date. You should enter a date here that is the date you want these Quotes to be good through.
You can change the good-through date on individual quotes after the conversion is complete. To call up a list of Quotes in Sage 50, select Lists from the Sage 50 Menubar. Then select Customers & Sales, and then Quotes.
To edit a Quote from the List window, highlight the Quote and select Open. This will open it and you can change the good-through date. Click Save to save the changes.