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This would be a very useful thing."
Although the Spreadhseet route has the benefit of being able to save the results for comparing scenarios or just coming back tomorrow to finish it off!
The Web route, provided using CGI/Backend processing rather than JavaScript, allows Navitron to harvest the juicy data of what everyone is calculating, which could be helpful for business planning I suppose. You might just find that "Buy 6 panels and get the 7th free" is just what everyone wants

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with the aid of my own personal spreadsheet teacher Kristen"
yeah, well that's very kind of you to put it that way, but apart from a Database forum, and the odd occasion when I can answer a computer question, I'm a net Consumer on the Internet (sorry about the pun!), so its nice to be able to give something back, particularly given all the very useful help you've given me on this forum.
Kristen