I've been spending most of the last couple of weeks dealing with "what happens when the flu on an oil furnace becomes blocked and the soot backs up through the house's vents. Everything and I mean everything is covered in a fine layer of soot. Inside the drawers. Soot. Inside everywhere. Soot. Furniture, carpeting. Soot. (I've been cleaning the house in my sleep for the last week)
You can't wash it off with soap in water, you have to spray with something that has a degreaser in it and wipe it with paper towels. I've gotten it mostly cleaned and put the first coat of "Kills" on the ceilings and walls. I've turned the corner and it's starting to look better, but there is plenty left to do.
If there is a good side, it's that I don't live on our farm, the house is our Deer, turkey and some-time poker camp. Still, the place is special to a lot of people. I was devastated when I saw it.... feeling better about it now as things get cleaned up.
Keep life simple...if you hear hoofbeats, think horses, not zebras.