The Hammers have been pushing hard to put a deal in place with Sassuolo for the Italy international and have made big progress.
Further talks will happen this weekend, according to Italian broadcaster Sportitalia, with the focus now on the bonuses that West Ham will pay.
It is suggested that West Ham will pay between €42m and €43m, including bonuses, and all parties are optimistic about an agreement this weekend.
The intention is that Scamacca can arrive in London either on Monday or Tuesday to undergo his medical checks.
West Ham believe that the striker is perfectly suited to the Premier League and want to wrap up the signing.
Paris Saint-Germain are also interested in Scamacca, but have put their pursuit on hold and it is claimed they need to offload players to proceed.
And now Scamacca looks bound for West Ham and, barring any hiccups, is expected to be undergoing his medical early next week.
