Kevin Costner's estranged wife, Christine Baumgartner, may face an uphill battle in their divorce following the Oscar winner's courtroom victory Wednesday. 

A judge ordered Baumgartner to officially vacate their Santa Barbara-area estate by the end of the month despite her request to remain in the family home through August. In addition, Judge Thomas Anderle sealed portions of the premarital agreement.

Kevin and Christine were married for 18 years and have three children together. She's requesting $248,000 per month in support, in addition to Costner fully covering the children's private school tuition, 100% of their health care expenses and their extracurricular activities and sports.

In his initial declaration, Costner claimed to have deposited $1 million into her account as part of their pre-marital agreement. The agreement also stipulated she receive a total of $200,000 upon marriage and after their first anniversary. Costner said that sum has now grown to "$1,450,000, which she can use at her discretion, including to find alternative housing."

Christopher C. Melcher, celebrity lawyer and partner at Walzer, Melcher & Yoda, told Fox News Digital that while Kevin can continue contesting the legal battle, Christine only "has one chance to win" as she claimed to have no monetary funds or income.

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Kevin Costner and Christine Baumgartner attend red carpet event

Kevin Costners estranged wife, Christine Baumgartner, filed for divorce in May. (Amanda Edwards)

"Kevin can afford to lose $1 million fighting this; he could afford to even pay the support if he loses it," he said. "She has one chance to win. She doesn't make this kind of money. She doesn't have these level of assets."

Costner has proposed to pay roughly $52,000 per month. Her request was submitted following a forensic accountant's report showing Costner's actual gross cash flow for the 2022 calendar year as $24,518,887, or $2,043,241 per month.

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"He can suffer that loss much easier, probably without even feeling it really at some level, but it would be devastating to her," Melcher said. 

"So the magnitude of the risk is higher for her than him, even though they're fighting over the same amount of money, because he's always going to be rich. Doesn't matter how this turns out. I think that she may have overplayed her hand, that the time to settle would have been before she filed where she could have kept this quiet, which would have made him happy."

Kevin Costner and Christine Baumgartner walk red carpet at Hollywood event

Christine Baumgartner is requesting more than $200,000 per month in support from Kevin Costner. (Frazer Harrison)

Melcher insisted Costner "shouldn't get carried away" either, because if the premarital agreement is dismissed on a spousal support provision in the court, Costner would be responsible for maintaining her marital standard of living, "which is an enormous amount of money."

"Kevin can afford to lose $1 million fighting this; he could afford to even pay the support if he loses it. She has one chance to win. She doesn't make this kind of money. She doesn't have these level of assets."

— Christopher C. Melcher, attorney

Sophie Jacobi-Parisi, partner in the Matrimonial & Family Law Practice at Blank Rome, said a resolution between an estranged couple out of the courtroom is always an easier solution.

"A private settlement is always better, especially when so much of their split is already in the news," Jacobi-Parisi told Fox News Digital. 

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Christine argued that the "Yellowstone" actor was being disingenuous with his claim of "doing the most [he] can reasonably do to make a divorce as seamless as possible for our children" as his actions showed "precisely the opposite" when he "sought to evict his wife and children from their home, and he now offers to pay child support of $51,940 per month." 

Kevin Costner wears black suit at wedding to Christine Baumgartner

Kevin Costner and Christine Baumgartner were married for 18 years. (WireImage House)

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"I would think that she will continue to seek the amount of support she feels is necessary to support herself and the kids, particularly now that she has to move out of the marital house, per the prenuptial agreement," Jacobi-Parisi said.

Costner has denied the allegation that he is "kicking" their children out, noting the kids will be in the home "during the time they are in my custody."

The "Dances With Wolves" star and Baumgartner both filed for joint custody of their three children: Cayden, 16, Hayes, 14 and Grace, 13. A hearing is set for July 12 in the child custody case.

"I would think that she will continue to seek the amount of support she feels is necessary to support herself and the kids, particularly now that she has to move out of the marital house, per the prenuptial agreement."

— Sophie Jacobi-Parisi, attorney
Kevin Costner and his wife Christine Baumgartner at Oscars party

Kevin Costner cut off estranged wife Christine from accessing joint credit cards. (Getty Images)

Baumgartner said his $51,940 proposal was "inappropriate" for a number of reasons and stated the amount is only "24% of guideline," and equivalent to 2.4% of his 2022 cash flow available for support.

"His proposed support is less than the monthly rent he received for one of his guest houses, and less than the $68,000 per month he committed to paying in his declaration filed on June 8, 2023 in connection with his request for a preliminary injunction," she argued.

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"Kevin’s I&E (income and expenses) states that his own monthly expenses, which includes the children when they are with him, are $240,000 per month. This is nearly five (5) times the amount he thinks that Christine should have to provide for the children when they are with her."

Kevin Costner in a brown suit looks off in the distance with his wife Cindy in black in California

Kevin's divorce from ex-wife Cindy Costner cost him $80 million (Ron Galella Collection)

Meanwhile, Costner claimed Baumgartner charged "over $100,000 in attorney and accounting fees" on his credit card since April without authorization or his consent. 

As a result, on June 16, he canceled her companion card and placed a cap of $15,000 per month to be used in case of emergencies for their children, according to documents.

Due to the vast difference in resources available to the parties, Christine is also requesting that Kevin advance an additional $350,000 in attorney’s fees and $150,000 in forensic costs," with payments made to a trust account before Aug. 1.

"Kevin asserts that he should not have to pay fees and costs for Christine to challenge the validity of the PMA [premarital agreement]," her lawyers argued. "He also regularly claims that the PMA is valid and that there is no evidence to the contrary. This is the legal equivalent of whistling past the graveyard."

Baumgartner also responded to the courts that she has "not accepted the funds that Kevin attempted to transfer and requested they be returned pending that determination. Accordingly, the funds deposited in that account continue to belong to Kevin, and there is no reasonable explanation for Kevin’s insistence that Christine use those funds for fees."

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