Third party companies who have contracts with large courier companies are able to pass on massive discounts to eBay sellers. All these suppliers accept PayPal so no credit/debit card is required and you can use the funds from the sold item from PayPal to pay for the courier.
Medium/Large sized items work out alot cheaper than using Royal Mail services and offer pick up/3 delivery attempts/tracking and insurance.
These suppliers have large contracts with DHL/Interlink Express/DPD/UPS/FedEx/Hermes/Yodel/City Link/TNT) which means you save up to 90% off the prices listed with the couriers direct.
**PLEASE NOTE** Always pay the extra for insurance. Most suppliers offer up to £50-£100 as standard, but if you're item is worth say £500.00 you are better off paying the extra for added protection for you and the buyer.
Please google 'parcel couriers' or 'parcel delivery' and compare the prices/services offered. Remember to look out for standard insurance & standard tracking.