Had a client try and screw me over. He hired me to build his website then asked for so many more tasks then what we signed for. I build the website on his server because it was going to be 3000 pages plus. Now this client has locked me out of his ftp, hosting, and backend website. He still owes me $1200 and is not emailing me back or picking up my calls. His website is complete except for some pages that need to be added. Negative SEO? Hacking? Not sure what to do but since he screwed me over I want to do the same to him. Any suggestions?