******* Legal Advice Needed ASAP ********

I am not sure I follow the whole story so this may not work for you.

Take the $700 he is willing to pay based on 6 pages then give him six pages of what you created. If its not complete its not your fault because that is what he paid you for.

If nothing is in writing he would not have a leg to stand on in court AGAINST you. He may goof and try to use the emails you don't have against you but then you can use them back in your favor.

Also, explain to him how difficult it will be to find another developer who will work on his site if he develops any problems or wants to upgrade later. He should see the light soon.