I did a project for a client (it was around 3000$). It was monthly support project and as per agreement he has to pay monthly 1200$. But for 3 months, he didn't pay anything. First time, he literally cried over the call, he has financial problem he can't pay this month...but he will get his salary very soon then he will pay. So I trusted him (here I did mistake) and I continued his work. But After 3 months also he just paid only 600$ and again he started crying. This time I stopped my work and started asking for rest of the amount. I sent him unlimited mails with reminder but he never responded. If I call him he always pick up my call and says this time he will definitely transfer my money.
My client was an employee in a reputed company and I was doing his job after taking his half salary. (I don't know how did he get that job even).
How can I screw him up legally? I have just our communication mails.