Apparition

[severelysigune]

No: HPFGUIDX 91044

Arya wrote:

<snip>
<<Why do Order members arrive at HQ via the front door and even ring 
the door bell, waiting for someone to let them in when Fred and 
George show us that Apparition is possible within the house?
<snip>
Is a just something that allows them to Disapparate and Apparate 
while remaining within the house?  If they can do this, why do Order 
members not simply pop in and out without risking being seen outside 
as they enter or take the time to wait for someone to answer the 
door?  
There must be something that makes it impossible for the Order 
members to not pop in and out--it's far and away a better way to 
travel and less risky than arriving by the front door. >>
<snip>

Sigune here (without answers, alas, and straying slightly off topic):
Personally I do find it rather reassuring to see that it is 
apparently impossible to Apparate inside this house when you travel 
there. I have often wondered while reading how wizards and witches 
secure their privacy. 
I mean, Floo sometimes works as a kind of telephone; but the person 
who tries to contact you either stands right in your fireplace or 
peeps directly into your house at least. Likewise, a person can just 
Apparate into your house. How to ward off unwanted visitors then? A 
Muggle can simply refuse to answer the phone or the doorbell; the 
person calling cannot know the other one is at home or not. I would 
hate the idea that it is possible for someone to literally pop in at 
any given moment, whether you feel like entertaining them or not.
So:
Would there be a) restrictions to Floo use (e.g. can you 'shut down' 
your fireplace?); b) courtesy rules (e.g. you are supposed to 
Apparate at the front door rather than inside a house when you go on 
an unexpected visit); c) specific (household; not just the very 
intricate ones no doubt at work in Hogwarts) charms to keep people 
from dropping in at random; d: other?

Yours severely,

Sigune