Optimize shipping structure

[martobg]

Hi all,
I am about to start up my own company that will sell products online and I'm trying to determine the best shipping structure that will maximize my profits.
For now, I have come up with the following shipping structures:
1. All orders have the same, fixed shipping charge
2. Each order has a separate shipping charge depending on its weight
e.g. 0-5kg - $5
5-10kg - $10
above 10kg - $15
3. Each order has a separate shipping charge depending on the amount of the order
e.g. 0-$20 - $5
$20-50$ - $2
above $50 - free shipping
4. Fixed shipping charge plus a set fee per kg
e.g. $10 + $0.50 per kg

These are the various shipping structures I have come up with for now. I welcome any other suggestions.

So, my questions are: How can I evaluate the effect of all these shipping structures on my profits using Solver in Excel 2007?
What information do I need - shipping charges from the delivery company, my products' prices and margins, what else?
What is the best way to organize all this information in Excel so I can make the right call which shipping structure to choose?

I would welcome any suggestions, excel templates, tutorials, tips, etc.
Thank you in advance.

 

[martobg]

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