This is kinda late to be asking this, but in this case when you talking about painting buildings, lawyers, etc are you talking about painting as in directly applying paint onto them or painting them on a canvas
Fest can have either meaning.
Who is painting the beautiful building - marked as incorrect
Is this paint as in painting the building on a canvas or, painting as in painting the building itself?
Could be both.
Who paints the beautiful buildings - marked as incorrect
Yes - because the Hungarian is singular - just "building" not "buildings".