Wouldn't the cost of a repaint, if done internally, be fairly negligible as it's essentially just material cost?
The paint, believe it or not, isn't actually that expensive, in fact I'd be surprised if the raw paint cost more than £300.
Labour is the main reason the price of a repaint is so expensive, but if you've already got a fairly competent bodyshop on the payroll, then it makes it much cheaper
RE: Repaints into 2019 fleet livery