3. Philippe Coutinho - £8.5 million
When it comes to pure Return on Investment, the diminutive Brazilian would be atop this list. However, while he did perform great things on the pitch, he is more remembered for his exit over anything else.
He arrived in the winter window of 2013 from Inter Milan where he just could not nail down a starting role for the European champions. He scored on his Reds debut against Swansea and was off and running from there.
He formed a strong partnership with Luis Suarez as both players thrived in creative areas and were often of the same mindset.
We of course all remember his long range goal against Manchester City at Anfield when there was a thought of a Premier League title in the future. He recorded 14 G/A in the 14/15 season before adding 19 G/A the following campaign
The good times kept rolling for our No. 10 until he stunningly handed in a transfer request in late summer of 2017. The rest is of course history as he was sold to Barcelona for £142m.
These funds famously helped pay for the likes of Alisson and Fabinho to join the club thereafter and form the spine of the team that would win everything possible.
Coutinho had 54 goals and 43 assists from 201 matches played for Liverpool. While he did not win any trophies with the club, he was a dynamo and more than proved his worth. It was a win-win from a Reds perspective.