As one of the hottest candidates for the 2018 NBA Championship, the Golden State Warriors have already been confronted with tough games and successions of tactics targeting their weaknesses. Furthermore, an invisible enemy is also approaching the defending champion: The inevitable high cost of team building. A league source told ESPN that financing is "the only factor that could dismantle this super team."

For the 2017-18 NBA season, the Warriors have already spent about 168 million US dollars on salaries and luxury taxes. And that number may grow to over 1.1 billion in the 2020-21 NBA season in total if the Warriors want to keep all of their core players, according to ESPN experts.

In the summer of 2018, the Warriors will meet the first task: What contract should they give Kevin Durant?

There will be three options for Durant. 1. To continue the second year of his current contract which is worth approximately 26.25 million US dollars; 2. To sign a new two-year contract at about 30 million dollars a year and with a player option for the second year; 3. to sign a four-year contract worth some 158 million dollars.

If Durant chooses the first two, he can enjoy the benefits of "Qualifying Veteran Free Agents" (also known as "Bird Exception") in the summer of 2019 when he can sign a five-year contract worth 219 million dollars.

If KD chooses to sign a relatively "cheaper" contract, like he did in the last summer to help his team stay competitive, he can only help his boss save some luxury tax money.

The other hard nut the Warriors will have to crack is to decide who will enjoy the benefits of the Designated Veteran Player Rule (DVPR) by signing a super contract worth over 200 million dollars? Clay Thompson or Draymond Green?

If Clay and Green are elected into Team of the Year for this season, or Clay gets elected while Green receives Defensive Player of the Year Award (DPOY), they will meet the standard of DVPR successively in the summers of 2018 and 2019.

NBA requires that until the current Collective Bargaining Agreement is due in 2024, one team can have two DVPR players at most. If Clay Thompson signs a five-year contract worth 219 million dollars in the summer of 2018, he will take about 37.8 million dollars in the 2018-19 Season. If he does not meet the standard of DVPR, he can also sign a five-year contract worth 188 million dollars and receive 32.4 million for the first year. 

The same applies to Draymond Green. Whoever of these two gets an expensive five-year contract will take a huge bite of the Warriors' budget for salaries and luxury tax.

The Warriors will have to pay over 100 million US dollars for the salaries of Stephen Curry, Kevin Durant, Draymond Green and Klay Thompson in the coming years. This has left almost no extra money to build a quality bench.

Young players like Patrick Macaw can sign four-year contracts worth about 40 million dollars at maximum. Old players including David West, Zaza Pachulia and JaVale McGee can sign new contracts worth of several million. If the Warriors choose to seek their replacements from the free agent market, they can offer no more than a 5.3-million mid-level exception and minimum wages.

Assuming Durant executes his 26.25-million US dollar contract, the Warriors will have to pay approximately 147.3 million US dollars for salaries and 61 million US dollars in luxury taxes in the 2018-19 Season. If KD signs a new 30-million US dollar contract, the luxury tax will grow to 77 million US dollars.

The money-burning action is just getting started. If both Durant and Clay sign five-year contracts with top salaries in the summer of 2019, Golden State's total wages will be 178 million US dollars, accompanied by a luxury tax of 225 million US dollars for the 2019-20 Season. Even if these two are willing to cut their contracts by seven million, their team will still pay 164 million US dollars for salaries and 133 million US dollars for the luxury tax.

Though in the 2020-21 season, Golden State can pay relatively less thanks to the probable rise of the luxury tax standard from 131 million US dollars to 136.7 million US dollars, the team will still pay 177 million US dollars for luxury tax, making the total budget about 354 million US dollars.

In total, the Golden State Warriors will have to prepare a budget of about 1.13 billion US dollars in the coming four years, if they want to keep all of their core players.