are you referring to the haunted house in eterna woods? if it is, there is a Pokemon you can catch inside but only between 8pm to 4am and you need to find the television in the back of the house. once you are there and it is the time you can catch it, then thump the television and you can catch rotom. rotom is at level 20.
That is for decoration.
He is in canalave city in the house right below the Pokemon centre
Yes you can you have to beat the elite four and then get the national pokedex.
The house above the pokeshope in canalav city
The day care lady's husband is in front of the house.
if you have the special key, it is at the very back
Rotom, He can be found in a flickering tv in one of the back rooms in the haunted house in the Eterna forest.
go to oaks house after national dex complete
At night in pokemon platinum go to the haunted house using cut and go into the upper floor/lower floor and go into the room that have the TV and if it is night , as I mentioned go click/ touch on the TV and then rotom will appear!
nope but you can on Pokemon platinum
When you complete the Haunted House, you can copy the costumes of the ghouls at the party. There are no free Halloween costumes in the Store.
You can get rotom by in the haunted house near eterna city and after 8pm and go to the one witch has the scary picture on and press A at the tv and you should get rotom. Rotom can be caught by a normal great or ultra ball
there aren't any Pokemon inside the house
In celestic town
POOPS u can liv in it
Go to Celestic town and her house is near to the left of the Pokemon center.
If you're talking about Gengar, then you must go to Eterna forest's haunted house with the Pokemon Emerald game inserted. Although, he is rare to find. Or the other preference would be to use the Global Trade Station Trading Terminal.