Assistance Setting Up Different Shipping Fee

Hello,

I would like to get some assistance on what I am trying to accomplish for my shipping fee.

Here's what I am trying to do:

I sell different products, and based on the product's nature, I determine how much the shipping fee is. However, I also sell products that I would like to have a flat shipping fee if you purchase multiple products.

I sell groceries, so let say one customer buys toothpaste, lotion, soap, shampoo etc. I want this specific order to have one flat shipping fee.

However, I also sell big items such as electric fan, TV and furniture and would like to set a different shipping fee for this. If I use the weight option for shipping, I have no clue as to how to set the orders for grocery to have one flat shipping fee regardless of how many items you purchase....

I hope this make sense....

Any help will be greatly appreciated!

However, I also sell big items such as electric fan, TV and furniture and would like to set a different shipping fee for this. If I use the weight option for shipping, I have no clue as to how to set the orders for grocery to have one flat shipping fee regardless of how many items you purchase....
Have to account for the case where there are normal items and large items in the same order

This will require that you add some conditions and calculations to the selected shipping module

Here is one where the UPS module was modified and the principles are the same for any module

http://www.zen-cart.com/forum/showthread.php?t=165331