United's purchase back of Pogba at 89 million Pounds and PSG's purchase of Neymar have ruined the market price barrier.
Now, a decent player would be worth 30 to 50 million pounds. A fringe player would be at least above 10 million.
A good player would be in the range of 70 million and above and a star would be anybody's guess.
Talking about Martial where the lure by Spurs now. Should we sell him. I think not at this moment. Let's develop him further and fetch a big return. At this moment nothing big from Spurs is going to come in and with his wages at United, Spurs can't offer him much more. He has still some years left in his contract. Would he force a transfer and hand in a transfer request as what Coutinho did. I doubt so, as he is far from being a finished product and not many clubs will come in with a big offer. Clubs would hope to come in with a steal. Clubs like Juve or Spurs cannot guarantee him playing times other than telling him that he would most PROBABLY get more playing time there. Wages much more than what United is paying him - I guess not. Which makes him hesitant in handing in a request for transfer. Now, if Martial were to develop to become a really good player and when clubs like Barca or RM comes for him, I bet his head will turn and would hand in a transfer request if we refuse to sell him like what Coutinho did.
Reason being, he would be in a team that are more incline to winning - not Spurs who refuse to upgrade as what Danny Rose is firing away. The business is more important than the ambition of the club. Would Martial want to force himself out to join a club that is not fighting for the title but a place in the top 4? He might as well join Arsene Wenger - his countryman.
Talking about Coutinho, would he be sold this season. I think most probably - yes. FSG was sold into believing in Klopp with their Summer pre-season. I believe FSG would be tempted by the monies on the table. It is Klopp that is promising them success and the building of the team. Yes, Klopp has added in a few players that he wanted - his first choice with Coutinho, Mane, Firmino, Lalana to beef upon. Klopp doesn't go for second choice players. So he refused to sell Coutinho as he would find it difficult to find a proven product that he already had. So FSG lanlan has to turn down the offers by Barca. Now that Coutinho had sent in his request for transfer and getting a member of his family to publicly criticize Klopp. He burns the bridge with Klopp as Klopp is a very passionate man and he would not want one that betrayed him and publicly criticize him. Klopp has said that he would leave Coutinho's matter to the owner. I believe the owner before selling him when Barca comes with a new offer of around 100 million quids, will ask Klopp and I think Klopp will not force the owner to retain him.
FSG knew full well that with Barca, they wouldn't have gone for Coutinho with such urgency if not for their losing of Neymar and their having the 198 million quids in their hand. Barca doesn't want to fall behind RM and therefore needs to beef up. It is a now or never case for Coutinho and Liverpool. Liverpool may keep him for another year but would they attract another offer of 100 million quids? I guess not and FSG are not stupid. They know this. Likelihood is that Klopp would be serious thrashing through the market to find Coutinho's replacements.