Hope it never happens, but if you ever go through a divorce do NOT handle the negotiations yourself. Your view of the art of negotiation is rather worrying.
We both know that football is utterly detached from any semblance of common sense or logic, see 50m for Kyle Walker as evidence of this.
You really want a player you pay the price. Monaco in this case hold all the metaphorical cards, they do not need to accept any offer we make, we simply need to pay them their asking amount - or not.
The price they quote you is not the lowest they will sell for. Finding the lowest they will accept, putting pressure on them through the player, agents etc. That is negotiation in football.
They could have got the price for Walker down to 40 million and it still would have been absurd. THat is just bonkers from a bonkers club.