Another less direct technique for delineating types of unenforceable transactions stems from the common law doctrine. It holds transactions that are not enforceable if there is no negotiated exchange. This class, for example, would include promises to make gifts. The approach tends to be comprehensive and to consider certain types of transactions as suspect when there is little or no practical justification. For example, it is not clear that an option agreement between two businessmen should be managed differently from many other types of business transactions. There is a strong argument that common law management of trade options, trade trade trade compromises and other trade transactions without an exchange element makes more sense than the expression of legitimate political concerns. The russian sales contract group includes, with a general sales and sales contract, a number of other contracts, such as retail sales, delivery contracts and real estate sales. For each type of sales contract, the specific provisions that apply only to this type of contract and the general rules applicable to all sales contracts apply. To enter into a sales contract, it is enough to reach an agreement on the purpose of the contract (i.e. the items to be sold).
Some types of individual sales contracts also require agreement on other conditions. For example, for the conclusion of a commercial delivery contract (delivery), the parties agree on delivery terms such as Z.B, delivery dates and quantities of each shipment. The sale of real estate requires explicit consent to the price. The sale of residential real estate also requires a provision relating to the rights of third parties, such as members of the seller`s family, who, by law, retain the right to occupy the land despite the transfer of ownership to a new owner. It is clear that there is no balance between the obligations of employers and workers. In addition, there is a complex procedure for legalizing employer-employee relationships, especially when you start developing your business. Many people deal with these issues using civil law contracts. Civil law implies contractual freedom and gives carte blanche to employers who want to earn an honest living by running a business. Thanks to freedom, some people are wrong, especially people in government. Contract law is based on the principle of pacta sunt servanda formulated in indenkisch (“Agreements must be respected”).  The Common Law of Contract was born out of the now-disbanded letter of the assumption, which was originally an unlawful act based on trust.  Contract law is a matter of common law of duties, as well as misappropriation and undue restitution.
 Article 429, paragraph 1, of the BGB not only defines framework agreements as a separate type of contract, but also stipulates that a framework agreement can define the general terms of the contractual relationship of the parties, while the details are reflected in separate agreements that the parties must enter into under the framework agreement.