I did have them sign a contract to do the work originally and I have them sign an invoice and send it along with the payment when it is done. It is really easy to remove those links on their site, but the simple fact is that I do not plan on doing that for them and nothing in the contract mentioned this. Also I do not plan on telling them what software I used. What is the point? I think they assume that they can get the software and update. People are morons, because HTML and all the programs I use to create sites take a very long time to learn and to master.
Thank you for all your responses. Excellent forum!
Open your mind