My question involves business law in the state of: California
I was served with papers today to appear in a Southern California Small Claims Court (I live in Northern Cal).
I am in the mortgage business and a friend of mine (Roger) who worked in a brokerage in Southern Cal called me one day and said he had a friend (Steven) who worked with him that had a question. Roger put Steven on the phone and he proceeded to tell me that he had a loan that he was unable to get done at his brokerage and indicated that he really wanted his customer to be able to get help. He asked if I'd be willing to take the loan and run it through my shop.
I said no problem and got the information and over a 4-6 week period closed the loan. To my dismay, I started receiving phone calls after the loan funded from Steven telling me that I owed him money for sending me the loan. I told Steven that there was no agreement in place and had I been aware he was seeking compensation, I would not have agreed to do the loan in the 1st place (it was a very small loan and not much money in it, $3100 gross to be exact).
Steven then enlisted one of his associates to begin calling me and sending me text messages threatening me with bodily harm even up to the point of telling me he had my address and saying he was going to come and kill me if I didn't pay.
I continued to try to diffuse the situation and he would repeatedly call. (up to 30 - 40 times a day) I informed Steven's associate (Bruce) that regardless of whether or not there had been an agreement in place, none of this was his concern and he proceeded to tell me that it was "his" money.
I regularly work with 2 different mortgage companies (Company A & Company B). He was under the assumption that I did the loan thru Company A and began calling them and telling them that we had an agreement in place and that I owed him $1800 (a number I can only surmise that he pulled from thin air). I actually ran the loan through Company B unbeknownst to him and in reality, my name is nowhere to be found on the loan because it was in a state I wasn't licensed in and had to pay a fee for a licensed individual to process and book the loan.
After 2-3 months of back and forth, I received a "Plaintiff's Claim and ORDER to Go to Small Claims Court" that was sent to Company A's headquarters (which I never actually worked for or booked the loan) and they forwarded it to an associate of mine at Company B whom they knew was acquainted with me. (I was never personally served.)
The suit lists me as the Defendant and Steven as the plaintiff. (with no mention of Bruce)
My question is this to anyone who may offer an opinion: since there was no written agreement or contract at any time, is there basis for him to win this case? Also, what recourse do I have in fighting a baseless claim? Is there any way that I can avoid having to spend money making a 500 mile trip to defend myself if he has nothing to base his claim? Also, if I do make the trip and subsequently win, can I then counter sue him for my costs/damages to defend a frivolous lawsuit?
I understand (somewhat) that I can sue him as well (using form SC-120), but what would I be able to sue him for? A frivolous lawsuit? Can I file my claim in Northern Cal so that he must travel here to defend himself as well?
I know this is rather long and I appreciate ANYONE and EVERYONE who has stayed with it long enough to read it in its entirety. Any opinions will be greatly appreciated. Thank you in advance.

