Section 83.020 - Retail installment contract requirements; exceptions(1) Except as provided in subsections (2) and (3) of this section, every retail installment contract shall be contained in a single document which shall contain the entire agreement of the parties including any promissory notes or other evidences of indebtedness between the parties relating to the transaction, except as provided in ORS 83.040, 83.050 and 83.140.(2) Where the buyer's obligation to pay the time balance is represented by a promissory note secured by a chattel mortgage, the promissory note may be a separate instrument if the mortgage recites the amount and terms of payment of such note and the promissory note recites that it is secured by a mortgage.(3) In a transaction involving the repair, alteration or improvement upon or in connection with real property, the contract may be secured by a mortgage on the real property contained in a separate document. Home improvement retail sales transactions which are financed or insured by the Federal Housing Administration are not subject to ORS 83.010 to 83.190.(4) The contract shall be dated, signed by the retail buyer and completed as to all essential provisions, except as otherwise provided in ORS 83.050 and 83.060. The printed or typed portion of the contract, other than instructions for completion, shall be in a size equal to at least 8-point type.