It’s not an unreasonable assumption, but still doesn’t make it right. It could just as easily be £3m in instalments and performance incentives making the deal worth up to £4-4.5m for arguments sake. Such a clause could be promotion which may not be realised. For example, Simms’ deal is worth ‘up to’ £8m, we haven’t paid any near that upfront.
Pretty sure Monaco included the £20m (or so) bonus for Martial winning the Ballon d’or when reporting the price of that transfer so take the publicly reported prices with a pinch of salt.
No mention of incomings mate, however I would question whether a 19 yr old right footed CB is what we need, unless we have a 2nd player in that position on the way in aswell.