My question involves business law in the state of: Texas
I have searched this forum and I am unable to find infomation regarding my question and I was hoping to find help here.
I am a small business and a regular commercial client asked me to put in several surveillance systems at his 2 businesses and his home. I was paid a deposit and paid the initial balance but they have yet to pay for the moves, adds changes and additional equipment they requested. This is going on 90 days and they will not reply by phone, email or in person.
I have tried to research on how to send a demand for payment and file a lien but i am very confused. Any help would be very appreciated.

