The manner in which your arrival is managed is listed on your accomodation ticket. There are two options:
1. The home owner/manager will bring the key to the accommodation and meet you on site.
2. On your accomodation ticket you will find the address of the home owner/manager where you can pick up the key.
The same applies to departure, unless you have made different agreements on site. On your accommodation ticket you may find a request to call the home owner/manager before arrival, to guarantee a smooth key transfer.