Where we offer other products besides our sub box, it would be really handy to set a figure for “combined” shipping like Etsy does. E.g. the cost for shipping a paintbrush could be set at 1.50 normally, but if combined with other items, I would set something like 0.20 or free.
I know we can set a maximum shipping figure per cart, but this doesn’t help. E.g. maximum for a cart with 5 paintbrushes should be 1.50 (instead of 5 x 1.50), but maximum for a cart with one book and one paintbrush would be much higher.