£10m will be the figure that the rumour site has lifted off transfermarkt (converted into GBP)I'd be pretty surprised if Boro even entered into negotiations at £10m.
I would expect that they'll want something in the region of £30m, but will ultimately settle for a fee in the £20m to £25m range.
Anything less than £18m and the buying club will be getting a bargain in my view.
Players rarely go for that if they still have reasonable time on their contract and the selling club don’t want or need to sell. Especially when the transfer is between clubs within the same division