Manchester United have already settled on a fee of £12.7 million with Torino for Matteo Darmian which could rise to £14.4m if the player reaches certain targets.
The final details of the deal are being ironed out and one of those involves paying a fee to AC Milan, who developed the player.
The 25-year-old Italy international was with Milan from 2001 to 2010 before being sold to Palermo and they are due roughly 5% of the player's transfer fee which amounts to around £287,000.
Darmian will become United’s second signing of the summer following the capture of Memphis Depay from PSV Eindhoven and they have also been in contact with Southampton regarding the potential transfer of Morgan Schneiderlin.
A £20 million bid was made for the player by ManchesterUnited two weeks ago but rejected by the Saints, who value the French international at £30m.
Southampton boss Ronald Koeman spoke earlier this week of his desire to get any potential deal done as quickly as possible.
"Two weeks ago, we had a Manchester United bid. It wasn't enough, wasn't serious, and there have been no more bids," he said. "Everybody knows the situation. I understand the player - if he can get a good move to a big one I can understand it.
"But I hope that if there is any business it will be soon, because it's best for the player and best for us. We have to prepare for what we'll do if we sell the player."