You need to hire an attorney to do this in Nevada. Its a tough case. If you have your checks going directly to the mortgage company that would be a big plus. It appears that Nevada is a two party recording state meaning you can't record someone without their knowledge (http://www.citmedialaw.org/legal-guide/recording-phone-calls-and-conversations). An attorney will guide you further on how to obtain evidence.
If you'd like to discuss, please feel free to call. Jeff Gold Gold, Benes, LLP 1854 Bellmore Ave Bellmore, NY 11710 Telephone -516.512.6333 Email - Jgold@goldbenes.com
Whatever "rights" you seem to claim seem to come after you've voluntarily chosen to make the payments in question. You are not in a good position to make a claim, especially without some writing(s) to show you both agreed to any of this.
Th fact that she paid you back the $6,000 may also be of help. Hopefully you kept a copy of the check. If not, try to get copies from your bank. The amount you are talking about is alot so would be worth pursuing based on breach of oral contract. Gather any witnesses you may have who knew the truth of what was going on. Do not record her without her permission, most likely you won't be able to use it anyway. Get an attorney to represent you since tis will be a superior court unlimited civil case. Good luck!
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