Summarize the following:
If there is a dispute between the two parties, then they may end up in court. However, you can also choose ahead of time to resolve your dispute using mediation. You should include an agreement to mediate in the purchase and sale agreement. Sample language could read: “Any dispute arising out of, or relating to, this agreement will be submitted to a private mediation service. Any cost of mediation will be shared equally between Seller and Purchaser.” The offer to sell doesn't last indefinitely. Instead, there is usually a deadline for acceptance. There is also a deadline for closing. You should include these dates in your purchase and sale agreement.  For example, you could write: “This offer is void if not accepted by Seller in writing on or before [insert time and date]. Closing of the sale shall take place [insert number of days] after Purchaser’s receipt of an abstract showing marketable title in Seller or title insurance binder showing insurable title in Seller. This offer is made at [location] this [insert date].”  Insert a signature line for the purchaser beneath this statement. You also need a provision where the seller explicitly states that it agrees to the contract. If the seller needs to pay a brokerage fee, then include that information here. Sample language could read: “The foregoing offer to purchase real estate is hereby accepted in accordance with the terms and conditions specified above. The undersigned hereby agrees to pay a brokerage fee of [insert fee amount] to [insert name of the broker] in accordance with the existing listing contract.” Then insert the date and a line for the seller's signature. This article describes a basic purchase and sale agreement. Your needs may vary. To understand if anything is missing, you should show your draft to a qualified real estate attorney.  You can find a real estate attorney by contacting your local or state bar association and getting a referral. Once you have the name of someone, call and schedule a meeting. Ask ahead of time how much the attorney charges.

Summary:
Include a dispute resolution clause. Identify the time for acceptance and closing. Add the acceptance by seller. Show your draft agreement to an attorney.