The reason 4 yellowing not much or none at all natural sunlight getting 2 doors & other woodwork & regarding why oil v waterbased is price waterbased nearly twice the price !
M8 why don't u just get painter in I know if it wiz me I'd want £100 to paint 3coats &£50 to fix u & plasters mess I would bring my drywall dustless electric sanding machine to make it smooth