Currently it’s impossible to have multiple people use your house because only the creator has access to the door. This creates a lot of problems for friends/clans.
I have a few different suggestions for this issue:
1st Suggestion: Allow the owner of the door (person who placed it) to type in the account names of people he wants to allow access to use the door.
2nd Suggestion: Due to the need of securing your loot…people tend to make 20-30 doors for 3-4 story buildings. Lots of doors means spending lots of time adding all the names of people. So one way to cut down the time would be to have a menu that shows all of the doors that you own (maybe you can add a unique title to each door you place so you can identify specific doors easier here…for example on the 1st door to your house you could call it ‘Main Entrance’ etc…), and possibly even having a little map next to this menu that shows where each door is located on the map by some little icon…this makes it so you can give people access to specific doors incase you have multiple houses spread over the map.
Reason for these suggestions: As the game grows, people will want to build and lock down a specific area on the map. To do so requires lots of people/friends. This will solve the headache of players having to build numerous doorways for the same entrance.
Also this can help with raiding. If your raiding a house with 3 buddies, and you put filler-doors after you break down a door, and say you die during the raid, your buddies can still continue the raid without you since they can have access to the doors.