It's that orangey/brown dust from their building works that has settled on all of my exterior windowsills. I tried and tried and to scrub it clean, but it looks like what's left behind has stained a rust now on them. Two weeks ago he said he'd pay for my car to be cleaned (as his builders didn't offer to cover my car) and I wasn't advised to move my car. Should I tell him about my windowsills now? They look like they're permanently stained/pitted now. I'm jus hoping they've got a clean up plan in place as my front/rear entrance looks like a building site.