Crystal Palace have agreed a £16m fee with QPR for forward Eberechi Eze in a deal that could rise to £20m.
The additional £4m are seen as 'achievable' add-ons, with QPR also having a 20% sell-on clause built into the agreement.
Eze, who scored 14 goals in 46 appearances in the Sky Bet Championship for QPR last season, is now on his way to Palace for a medical where he is also expected to finalise personal terms.
The 22-year-old was left out of QPR's matchday squad for Saturday afternoon's friendly with AFC Wimbledon, with the club keen to avoid putting him in an awkward position amid Premier League interest.
While Palace have struck a deal with QPR, Fulham, West Ham and Newcastle have all also expressed interest in signing Eze.
Speaking to Sky Sports News after Saturday's 3-0 win at Loftus Road, manager Mark Warburton indicated Eze would only leave QPR if the club's valuation was met.
"Any situation for any player is resolved when the value of a player is met, that's how you resolve a situation," Warburton said.
"You make sure the value is appropriate, the value is correct, and when that value is met we wish everyone the best of luck going forward. That's the way it is at QPR. Right now if it is not reached, then he's a QPR player. As long as we pay the wages, he's one of ours."
Analysis: Eze a unique talent
Sky Sports' Lewis Jones:
Eberechi Eze is an important player for QPR - in a number of ways. Not only is he without question their most talented individual, he also signifies the results of the change in business philosophy at the west London club. No longer do they haemorrhage money on big names, they have put in place an environment for young talent to flourish.
Eze - snapped up for nothing from Millwall - is a devastating ball-carrier, possessing a glide with the ball that only a unique talent can boast. This season he has added work-rate and tactical awareness to his game without the ball, which has triggered significant interest from the Premier League.
All the latest news, analysis and rumours from the window in one place.
The summer transfer window will run for 10 weeks from July 27 and close at 11pm on October 5.
A domestic-only window for trades between the Premier League and EFL then runs from October 5 and closes on Friday October 16 at 5pm. Follow all the news and analysis on Sky Sports News and across Sky Sports' digital platforms, including with our dedicated Transfer Centre blog.