Construction costs are currently skyrocketing

Is that a lot or a little now?

I am not a professional painter, but the combo Q4, painter's fleece and silicate is somehow questionable to me...

In what way is that questionable? Each on its own or the combination?

Somehow reminds me of a story a painter friend experienced at a customer’s place: He had a ridiculously expensive organic clay interior plaster applied and then wanted to cover everything with a kind of latex paint because "otherwise the wall would absorb too much moisture." The internet is a curse when people think they can derive knowledge from gathered snippets of information. Hope that’s not the case here :D