Liverpool have been heavily linked with a potential move for Alexander Isak, who could cost around £120 million. However, having spent £265 million already this summer, how can the Reds afford him?A lot of Premier League clubs have been dealing with PSR (Profit and Sustainability Rules) in recent years. As per this rule, a club can only show losses up to £105 million over a period of three years. However, as per Mirror, the Merseysiders can buy Isak and one more player this summer without breaching PSR guidelines.Liverpool have spent £265 million this summer on six players, with Florian Wirtz being the most expensive at £100 million. They have also signed Hugo Ekitike (£69 million), Milos Kerkez (£40 million), Jeremie Frimpong (£29.5 million), Girogi Mamardashvili (£25 million), and Armin Pecsi (£1.5 million). They've also brought in Freddie Woodman, but it was a free transfer.The fees mentioned above are without the performance-related add-ons, which are likely to be another £30 million in total. However, all these payments can be amortised for a period of five years. This means that Liverpool can pay Wirtz's £100 million in installments of £20 million each over the next five years. This can be done for all these signings.Moreover, the Reds are also set to see some sales this summer. Coaimhin Kelleher and Jarell Quansah have already departed. The likes of Darwin Nunez and Harvey Elliott could also leave, with Bayern Munich also pushing to sign Luis Diaz. This is further bolstered by the fact that they only signed Federico Chiesa last summer. Hence, the Merseysiders have been able to spend big this summer and still have room for more.Alexander Isak open to leaving Newcastle United amidst Liverpool interest: ReportsAlexander Isak has been linked with the likes of Liverpool and Arsenal for months now. However, Newcastle United are unwilling to sell their star man. The Athletic journalist David Ornstein reported on Thursday that Isak has told the Magpies that he wants to leave.The Swede has been one of the best strikers in the world in recent years, especially since joining Newcastle from Real Sociedad in 2022. He's scored 62 goals and provided 11 assists in 109 games for them. He also helped the Magpies win their first major trophy in 40 years, as they won the EFL Cup last season.Isak's contract at St. James' Park expires in 2028, and Newcastle have been trying to tie him down to a new deal. However, the Swede is now open to leaving this summer. Liverpool have signed Hugo Ekitike but are still interested in Isak. Arsenal, meanwhile, are set to sign Viktor Gyokeres.