6. Neymar | Value: £55m
Only a few people are aware of the exact figure Barcelona paid Santos - and several other parties - to sign Neymar last summer.
It was initially reported to have been around £48m - which, when you consider his age and potential, is a fair price for the Brazilian superstar.
Neymar hasn’t set La Liga alight this season, but he’s enjoyed a decent enough debut campaign at the Camp Nou, scoring 15 goals in 40 appearances.
Barcelona - and the rest of Spain - will be expecting much more from the 22-year-old next season. But if Barca chiefs were convinced it wasn’t going to work out for the South American at their club, they could still make a small profit by offloading him this summer.