Does anyone know the penalty of usury?

[Renee Ren]

Hi folks, I lend money to a friend last year in April for her flip in Mountain Baldy, San Bernardino CA. She couldn't get the property sold because of the lease land and some title issues. I signed a promissory note with her. She was supposed to pay me interest every month but she only paid me two months interest till now. I was ok with her last year but it has been 15 months and I don't think she can get the property sold so I want to put NOD on her property. I'm the 2nd TD. 1st TD is my friend as well he is ok for me to start foreclosure process.

I was in contact with a foreclosure trustee. I sent them my promissory note last week. Because I was charging 15% interest on my note she said it is usury and there is a penalty for that. She doesn't know how much the penalty is. I asked my husband(he is a real estate attorney). He said never heard of the penalty. 15% is usury but it causes problem only when borrower comes back suing me then if I go to court judge will ask me to lower it down to 10%. A person can only charge max 10% interest rate. The lady at trustee is not comfortable of working for me unless I lower my interest to 10% and deduct the interest I received from my principle. She heard that from a client's attorney. She doesn't know any code No. of penalty. 

Does anyone know the penalty of usury. I'm also looking for other foreclosure trustee. Can anyone give me a referral. Thank you.