I did the Imperial questline and installed the new Jarl in the city. He told me I was now free to purchase the house but his steward says.. that the house is not available do to a problem...?? Help!!

Did you complete Blood on the Ice.

I heard that if you install the new Jarl you don't have to. I guess that is not true. I have entered and exited Windhelm tons but I never see the guard in the grave yard..... Is there a way to add the quest using the console?