Go to building mode while in your house (go to the options menus with the wrench, then click on the house symbol, then turn on building mode from there). Then right click a door hotspot and choose the type of room you want to make (remember to bring money).
At a player owned house, someone who has a gilded wardrobe.
You can repair them at a Player Owned House.
Can only be done in a Player Owned House, simply by clicking it.
In someones player owned house with high level construction.
Look on the world list for Player Owned House Parties on them, those will be the worlds.
in a player owned house, cooking guild or the grand exchange off another player.
These would be placed in a Quest Hall.
Yes, you can build a Dungeon and place monsters in it, which you can then attack.
they consist of you inviting a group of friends over to your player owned house and hanging out and playing with the various things you have in your house
To get a mini-game in your RuneScape PoH (Player owned House) you need to create a games room then, with the construction level, you may create different games to play.
You can eat cake anywhere, the best place to make it and eat would be at a player owned house.
You cannot plume helmets in runescape. But you can use a full helmet with a herald stand in your Player Owned House, and there are treasure trail rewards with different coloured plumes.