During a real estate transaction, there are several steps that need to be followed so that everything goes smoothly. This regularity is important to ensure that the buyer owns the property and that the seller receives the price. However, many people have doubts about the concept and usefulness of a purchase and sale agreement and end up confusing the public deed with the property registration document, which is called a registration. The purchase and sale agreement is a document in which the parties will discuss the details of the transaction. This preliminary document contains important information such as: Personal data of the parties involved; Complete description of the property; Total value of the property and payment terms; Any clauses that may be necessary. The purchase and sale agreement PRECEDES the public deed and deals with more specific provisions about the transaction, and, even if there is a purchase and sale agreement, the property must have its public deed drawn up and registered at the Real Estate Registry Office. The public deed is an official document that is registered at the Notary's Office (not at the Real Estate Registry Office). Through this, the purchase and sale of the property is formalized before the Notary and provides legal security for the assets. The public deed confirms the purchase and sale agreement before third parties (since it will be registered at the notary's office). It will contain all the details of the transaction, such as price and payment method. At this point, the ITBI (real estate transfer tax) must be paid; without payment, the deed is not formalized. Finally, the registration of the property means the stage where the buyer is already in possession of the public deed of purchase and sale (which formalizes the transfer) and arranges for its endorsement in the property's registry at the real estate registry office. The Real Estate Registry Office is the office responsible for keeping the entire history of all properties in its region on file. The property registry is the document registered at the Real Estate Registry Office and functions as a birth certificate for the property. This registry contains the entire history of the property. It contains information about the location of the property, the size of the land, the previous and current owners, purchase and sale transfers, the deed that originated the transfer of ownership, improvements to the property, annotations of encumbrances, reservation of usufruct and other information that may be contained in the registry book of the Real Estate Registry Office. In other words, both the purchase and sale contract and the public deed are important at the time of negotiation, so that the purchase and sale contract may be waived when the payment is made in cash and there are no other particularities. The public deed, on the other hand, is essential to conclude the transaction, and ideally it should be formalized after full payment of the price or else it should be formalized with a resolutory clause, which provides for a condition that, when established in legal transactions, allows the transaction to be undone if the price is not fully paid.