Hey John,
I believe that the 50,000 number is incorrect. From what our publisher told us our VFP5 and 6 books were profitable books. They had very few returns which is a contributing factor to a books profitability. I think that a lot of computer books sell less than 10,000 copies. 50,000 books would be a great number to sell. The royalties at this volume of books can be very nice.

Thanks
Rodman