Do I need a custom shipping module?

I need to set up the shipping situation below and I'm wondering if there is a shipping module that can do this already or if I need to write/have one written? And if I do need to write one, any suggestions on an existing one to start with?

A note: While I have done programing in the past, I've never worked with PHP.

1> Each item to have it's own shipping cost. (I assume an extra field added to one of the mySQL tables, or a new table linked to the products.
2> A checkbox on each item that says "Ship free with higher weight/shipping cost item in same order". This being checked will zero out the shipping cost for the item if there is a higher weight item in the order.
3> Attributes to have their own shipping cost adders. i.e. If attribute X is picked, shipping goes up by $1
4> Product shipping override above (#2) also to override attribute shipping adders.

Thanks in advance,
Keith

The goal it to get the product list that is in the cart and processes each product plus their attributes for their weight and only save the highest one to configure the cost for shipping ...

If you used the Product Weight as the actual Shipping cost, you could then configure a shipping module that can do this ...

It would take some customization as you don't want all of the weight, like what the Per Unit perweightunit shipping module is doing, but you do need the highest weight, and not just the Product Weight but the weight of any associated attributes for that product that might have weight ...

Yes, you'll need a custom module - none of the standard ones will do that for you. You will need to modify the product edit pages in admin and either add a field to the products table or add a new table (a new table is the best approach for future upgradeability). You might be able to get away with using the existing attribute weight capabilty to specify additional shipping.

If you've not worked with PHP before, you'll have a steep learning curve - but your previous programming experience should help to at least develop the required logic flow.