Rose product shipping can be set on "per product" bases and can be set to either auto calculate or flat rate.
Mixing of both is also possible, so one product can be set to flat rate and another to auto calculate.
Auto calculate works by getting shipping prices directly from shipping carriers, currently we support USPS, UPS and FedEx. You can set product dimensions and weight for each product (and each product option) separately.
Beyond that eezio comes with a pretty flexible shipping rules that you can apply to alter shipping costs on "per order" level.
You can setup shipping rules based on order total cost, order item count, order total weight or destination zip code. Using shipping rules, you can charge a pre-set amount, add or subtract from the existing order shipping cost.
Please reply if I can be of farther assistance
Steve - eez.io support