In the past, I've setup Namecheap for them so I could transfer the domain between accounts if needed. If they knew how to setup the php scripts (back when I did

In the past, I've setup Namecheap for them so I could transfer the domain between accounts if needed. If they knew how to setup the php scripts (back when I did php freelancing), I'd send them the related archive of files. If they wanted me to set it up for them, I'd simply setup the hosting based on their needs and wants which I find to be quicker than putting together the documentation for them to do it themselves and supporting it if something breaks when they configure it.