We have an apartment building where one of the units had a grease fire a few months back. It's been "thoroughly cleaned" by a professional remediation company, although there is still quite a bit of black soot "stuck" to the walls. The rep from the remediation company told me that it's perfectly acceptable, and the primer will take care of it completely. They've suggested using Kilz Original (red & white can) for priming. Now, the more I read here, I wonder if I should be using something else, like a shellac, Zinseer, etc...??? Odor is concern, as there a number of other tenants in the building, but I do have access to a large air scrubber that I can vent to the exterior, but obviously I'd rather not have the odor too offensive if possible. I do have an account at the local Sherwin-William's as well, so that's certainly an option as well. Thoughts appreciated.........