In addition..........indicate under what state's law the document is written,

also, we always indicate that the agreement was prepared by the parties themselves, so neither party can indicate that the lack of conditions/terms is due to improper legal advice, and attempt to overturn the rest of the document,

And, also indicate that both parties had ample time to consult with whatever legal counsel they believed they needed prior to signing.........which helps to kill the concept that one party was coerced, and did not receive proper legal advice.

We also indicate the methodology of payment, as compared to just a price.  If there is a trade involved, we also put in the deemed value of the trade in, just so income tax problems are avoided.

Sometimes..........but not often........I include a statement as to when our insurance stops, so there is no dispute over an accident on the way home.

Warning...........I have two sons who are relatively successful practicing attorneys........who hoop and holler and cringe every time they find out I have done one of my own legal-type documents.   However, since I am smarter then they are, I continue to do things my way.