When it comes to agreements, there is nothing more powerful than a signature on a piece of paper. Ever since parchment and ink were invented, signatures have been used to make agreements legal. Although a document may be valid with merely a signature, it may not always be acceptable since today's standards lend as much importance to verifiability as they do to legality.
Make sure the language or content of the agreement doesn't violate federal or state law. Any provision contained within an agreement violating either party's civil rights, or any other law or statute, would be considered invalid and unenforceable. If you have concerns about possible violations, contact an attorney to prepare or assist with the preparation of your agreement.
Have the agreement signed and signatures acknowledged by either two witnesses or a notary public. Some documents, such as a deed, may require notarization with specific state language to be acceptable to title companies, attorneys or other parties relying on the documents. Although a deed or agreement may be technically legal with a witnessed signature, it might as well be an illegal document if it is unacceptable to those involved in the transaction. Notarization and witnessing are methods by which parties relying on the document verify its credibility. Even though some states don't require witnesses for an agreement to be legally enforceable, an agreement claimed by someone to bear a forged signature would be highly contestable in a court of law if not witnessed or notarised.
Record any agreement or contract to buy and sell real estate in the real property records of the county or jurisdiction where the property lies if payments are to be made over an extended period and no actual deed will change hands until paid in full. If a seller signs a written agreement to sell you a parcel of land and the agreement remains unrecorded, he may deed the property to another party in the meantime. If the state is a "race-to-the-courthouse" state, the purchaser named on the deed will have acquired the property and your agreement will become invalid or not legally enforceable when you try to acquire the real estate. You may still have rights to sue for breach of contract, but odds are that you will be unsuccessful in acquiring the real estate.
Confirm that the person signing the agreement has the authority to make the agreement. If he signs the agreement on behalf of his corporation, LLC or other entity, yet doesn't have proper authority to bind the company, the agreement may be unenforceable.
Retain the services of an attorney to prepare and oversee the execution of your agreement.
Because state laws vary, it is important to know laws pertaining to your agreement or to retain the services of an attorney familiar with contract law.