Check out this DIY video on Shipping with the US Postal Service, How to Calculate USPS Shipping Price. These are excellent shipping labels. I have been using these for years and am very happy with them. Absolutely zero issues, you get what you pay for!
This is my go to for 2″ clear packaging tape, have been using it for years with great success. I like to buy in bulk and save money so I opt for the 36 roll deal. This seller does have other options if you don’t want or need a large quantity of packing tape.