it depends on the quantity your buy and how would you like to ship them, by air or by sea.
But to have another company arranging these things will be better , usually, you can send an inquiry to supplier to get a rough cost for both. if by air express, if their price is ok, then you can just ask the supplier to ship for you. From my experience, most of suppliers do not have good resource of good rates, certainly, there are some supplier also offer great rate.
When you need your goods shipping by sea, you must not ask the supplier to ship for you, because the china forwarder will forward all the cost to your destination port, and they quote very cheap price to China suppliers. The best way is you find a forwarder at your end, ask the supplier to quote product price by FOB terms, give contact of your fowarder to the supplier to ship the goods.
If you want to save your work, you can pay for a little service fee to a sourcing agent for handling all these work. they can offer the service like Sourcing products, place orders, inspect the goods, arrange goods with supplier to warehouse, consolidate shipment, handling export, documentations, etc.
Good luck to your business!