[thesimon]

The Audi delivery thing is tested in Germany and basically all packages require signature. I can't recall any site where I was able to "presign".

If you miss your package, it'll get taken to a nearby store where you can collect it with an ID or it'll be given to your neighbour.

[kenrikm]

In the US USPS/UPS/Fedex usually will usually just leave it on the porch/in front of the door. If it's a package that you need to sign for you can print out a "Pre-Sign" form that you leave on the door and they will just leave the package.