I think not only are you entitled to recover the security deposit and rent, but if there are damages in excess of that amount, you can recover the damages as well. Even though you don't have a signed written agreement, the The lack of a written contract can be overcome by the concepts of promissory estoppel, detrimental reliance, and unjust enrichment. This situation arises when Person A relied upon the verbal agreement, Person A performed based on such reliance, and because Person B defaulted, such reliance is now to Person A's detriment. Where there is i) partial performance by Person A based upon the mutual promises, ii) Person A relied upon such promises to perform, iii) Person B's failure to perform would be to Person A's detriment, and iv) result in Person B being unjustly enriched, Person A can overcome the legal requirement that the agreement be in writing. Your situation would satisfy all the foregoing and the texts substantiate the prior monetary agreement between you.
If he won't pay you voluntarily, file suit against him. You can file any claim up to $7500 in small claims court with no need for a lawyer. Filing the suit will give you the collection options and leverage you need to collect the debt owed you. That's because once the suit is filed and a judgment awarded, you become a judgment creditor, and if he doesn’t then pay the judgment, you can have the sheriff serve a summons on him for a debtor examination. That forces him to meet you in court again and answer questions under oath about his assets. After that information is obtained, you have the power to garnish wages, attach bank accounts, have the sheriff seize other personal property, and/or place liens on any non-homestead property he owns to satisfy the judgment.
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