Carrier and Handling Fees:
After you've taken measurements and weighed your item you can visit these websites to compare shipping prices and delivery times:
Boxes and envelopes
Professional packaging will leave your buyers with a positive impression of your store. Avoid using old shoeboxes or used-looking boxes to ship your items.
Durable packaging is also important. Shipping can be hard on any item, so spending a little bit more money on the packaging can save you money in the long run. Shipwire, a fufullment service, recommends buying cartons and packaging that can protect your contents from a 4 ft (1.2 m) fall.
You can purchase your shipping materials from a variety of places.
If you're an eBay seller you might consider investing in eBay branded shipping supplies. You can purchase them here: http://stores.ebay.com/ebay-Shipping-Supplies
If you're looking for a cheaper alternative you can turn to wholesale suppliers like Alibaba to get corrugated cardboard boxes: https://www.alibaba.com/trade/search
If you sell a specialty item like jewelry or soaps, you can also get custom packaging that matches the item you are selling. This will add to the customer experience, potentially resulting in future sales and creating repeat business. Colored Boxes or Wine shaped boxes for items like olive oil, juices, vases etc.
If packaging your items becomes too time consuming, or your business grows to the point where you need additional help shipping your item, there are a variety of fulfillment services that will ship your items for you with professionalism and care.
Packing peanuts, bubble wrap, tissue paper.
Keeping your item secure doesn't end with the box it's in. Make sure you limit the amount of space within the box and secure breakable items in bubble wrap, crinkle paper, packing peanuts, excelsior, or tissue paper. Remember, the more empty space in the box, the more likely your item is to break.
Transportation to and from the post office
When you're first getting started most sellers drive to the postal office and drop off their items. Though, this isn't the only way. Many carriers offer schedule pickups for your items. This can save you time and money, especially if you live in a remote part of town, or have limited access to transportation.
Getting insurance on your item can be expensive and cut into your profit margin but when it comes to rare, expensive items, it may be worth the investment.
To find out more about shipping insurance, you can reference this article written by eBay: http://www.ebay.com/gds/Shipping-Insurance-What-you-need-to-know-
Personalized thank you notes or freebies.
Sometimes a hand written thank-you note or a small token of appreciation can go a long way. Invest in a personalized thank you card and put it in your package before you ship it. This will leave your buyers with a warm and fuzzy feeling about your brand.
Additionally, this can be an opportunity to upsell or redirect customers to your personal website, or show them other items you have for sale. Get creative and see the difference it makes on your customer retention and feedback.