According to reports, West Ham need to raise around £150m this summer.

One thing that can both help and harm this over the summer transfer window is the presence of sell-on clauses.

West Ham need to make a lot of money this summer; players like Mateus Fernandes, Crysencio Summerville, Jarrod Bowen, El Hadji Malick Diouf, and Konstantinos Mavropanos are all likely to leave.

Fernandes is the player we simply have to sell; with a reported £80m asking price, he could make up half of the money we have to raise in this transfer window.

However, one downside of selling Fernandes is his reported sell-on clause. As part of the £42m total fee to bring him to East London from Southampton, he reportedly has a 15% sell-on clause.

So, if we sell him for the £80m asking price, we would have to pay £12m of it to Southampton. A huge chunk of money when we are in the financial difficulties we’re in.

If true, this may mean we might be forced into selling an extra player. Maybe if we didn’t have this sell-on, we could afford to keep a Mavropanos, Soucek, or a Castellanos.

However, on the other hand, the sell-on clause could also benefit the Hammers. When we sold Gianluca Scamacca to Atalanta, we reportedly included a 10% clause. This means if his reported €30m move to Roma happens, we could be in line for a €3m payment.