Thank you. To sue in a state court, one needs to have a "cause of action." There are numerous causes of action, such as "breach of contract," "negligence," "fraud," "unjust enrichment," etc., as well as causes of action rooted in statutory law. Every state has their own although they are very similar to each other in every state because they all stem from the same common law. A pleading in Court needs at least one cause of action, although it is not unusual to have more than one.
Here, there would be two Defendants, actually. Seller would be liable for breach of contract. The elements of a breach of contract claim are: (1) the existence of a valid contract; (2) the plaintiff's performance or tendered performance; (3) the defendant's breach of the contract; and (4) damages as a result of the breach. Marketshare Telecom, L.L.C. v. Ericsson, Inc., 198 S.W.3d 908, 923 (Tex. Ct. App. 2006). The request would be the money lost, specific performance (if the court voids the sale) to sell to you, and whatever other relief the Court feels is equitable.
The Buyer would be liable under quiet title action under the Texas Property Code. This is less against the Buyer per se, and more to ask the Court to determine who should be the rightful owner of the property. If the Buyer KNEW or SHOULD HAVE KNOWN about the contract ahead of time, then there is a good chance the Court will void the conveyance.
This is all done via a lawsuit. While an attorney is not mandatory, one is HIGHLY recommended. Let me know if you need help finding someone.
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