Looking at the clothes in the wardrobe, which are all black/white/grey and red (apart from one or two rogue green tops), I would say that the current occupant has quite rigid/fixed ideas about colour choices, possibly to the point of OCD or similar. But fundamentally, there's a lot of red because that's what they like, and it's their house!
It's quite easy to see what the underlying house is like, and easy to imagine what it would be like with a more varied colour scheme and furnishings. If you wanted and could afford a 3 million pound house in Solihull!