I have a different perspective on this matter. I do agree, though, that it is likely that your only remedy will be achieved by going to court.
Unless your husband and his ex can take this matter back to family court where they were divorced for further direction by the court, this is not going to be easily resolved.
It is highly unusual that his ex would have had her name on the deed, but that a lender allowed your husband alone to take out a loan secured by the full property value. It wouldn't surprise me if she were a signatory to the loan as well, or that she at least agreed to allow her interest in the property to be mortgage on that loan (essentially became a guarantor of the loan).
When two parties own real estate and one wants to sell but the other refuses, your sole remedy typically is to file what is called a "partition action". This is a lawsuit which asks the court to order a property divided into parts, if possible, so that each side may go their own way with their own property, and if that it not possible than the courts are to order the property sold (actually at a public sale, like a foreclosure sale, which substantially reduces everyone's profit potential). In some jurisdictions, but not all, there is an in between step where the court can give each party the option to buy out the other (at a price as determined by an appraiser who works for the court, so the price will be deemed to be fair under present market conditions). If the parties won't agree to that, then it moves to the court-ordered sale mode.
The key point for you to understand from this process is that your remedy lies in the court system, and there is no possible way for you to accomplish that quickly. That means that your best course of action probably lies with finding a new tenant, and working on resolvering these legal issues over time when your backs aren't against the wall.
It is impossible to know from the facts provided what actual interest the ex-wife is supposed to have in the property. I am presuming that the ex-wife's interest arose as a result of a divorce proceeding, and so it is possible that under the divorce decree it dictated whether she has an equity interest, or whether her name was being left on title to secure some payment she was to receive as a part of the divorce settlement, etc. If her name remaining on the title to the real estate was for the purpose of assuring her right to receive some other settlement payment out of the divorce, then that obligation would survive this real estate matter. If on the other hand her name is XXXXX XXXXX title to the real estate because she is meant to receive 1/2 the equity when the property sells, then what equity she has depends on market conditions, which means that it could have gone up but it certainly can also go down. Unless it was a condition of the divorce that she receive at least $25,000 out of the sale of house, there should be no legal significance to that figure.
Lacking any other evidence, one would presume from title alone that she is a 50% owner (hopefully as a tenant in common) to the property. In normal situations, a 50% owner of property is entitled to 1/2 of profits from a property, and is responsible for 1/2 of obligations. If this matter is taken back before the divorce court, or before circuit court due to filing a partition action, then there will be a mechanism to present accounting for what has transpired and arguments for how you each feel that the proceeds should be divided.
The long and short is that despite the ex-wife's refusal to cooperate, you can force her hand. But it will likely cost you a trip to court way or another to accomplish that, which is not going to get resolved quickly.
And letting the property go to foreclosure may be a disastrous move, especially if your husband has any obligations to his ex under the divorce decree. If the ex is truly not on the loan, the negative consequences of the foreclosure will fall primarily on you, the loss will fall on you, the ex may or may not still have rights to compensation from your ex. I just don't see much merit other than ease in taking this route.
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The information provided is general in nature only and should not be construed as legal advice or to create an attorney-client relationship. You should always consult with a lawyer in your state.
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