If you send as first class mail package, you can get tracking for free if you use PayPal (or eBay) shipping. Otherwise, you can pay at the post office counter for delivery confirmation, which is the same thing. It is affordable.

You cannot track a letter sent at letter rates for these affordable price. To tack a letter sent at letter rate, you need to upgrade to certified mail return receipt requested. The price is so high that it is much cheaper to put it in a box and use the package rates.

Many here ship using an envelope and regular first class mail for under a dollar. That type of mail cannot be tracked.

Insurance is slightly more costly. You cannot insure a first class letter. You can insure a package. Some postage rates automatically include $50 or $100 insurance at no added charge - check the post office website for qualifications.