Some more information.
I have a table containing all the products.
There is another table containing additional options, each record containing the record id of the product the option relates to. So some products may have no additional options, some may have quite a few (no more than ten, probably no more than five).
My page will show the product and then underneath will show all the options available for that product, some free, some costing extra.
I don't mind whether a single item is added to the cart and all the options are extra fields for that item, or whether we have one cart item per option.
But, I want a single Add to Cart which does it all in one process.
I'm really struggling with this. Because the list of options is dynamic I can't see how I can put these into the cart.
One last thing is that, if the options are costing extra, the product total needs to reflect this, or - if we are adding each option has a separate item - then the cart total needs to. Either way, so long as the product and all the options are in the cart and the cart total is correct, I'm happy.
Your thoughts would be very much appreciated.