Hazard's addons could take the cost to over £150m according to the BBC* and that was with only a year left on his contract. Pogba will have 2 years left on his contract, will be younger than Hazard was when he made the move and he's the face of the club, we'll get what we ask for him.
* https://www.bbc.co.uk/sport/football/48548361
Let's see. Pogba's also more out of favor here than Hazard was at Chelsea. Don't think Real are able to splash money like that year after year neither. Maybe if they sell.
For a BBC article I think it's very light in detail about what allegedly makes up the fee rising to 150m. Only mentioned in the headline and under the picture, not even describing how it could rise to 150m.