What is in an Offer? An Ohio residential purchase agreement is a contract between the buyer and the seller of a residential property.The agreement must have a start and end date. An Ohio purchase agreement establishes the terms and conditions of a real estate transaction. Property Disclosure Form: Ohio law mandates this form, where you detail the condition of your property, including known defects. The purchase agreement attached here is a standard purchase agreement between the buyer and seller, for properties located in Ohio. Include the contact details and full names of both parties.