1) The transaction is incompetent citizen.
According to Articles 32, 33 CC incompetent recognized as citizens, limited in capability by the court due to abuse of alcohol or drugs, as well as those that are unfit to plead due to mental disorders, and therefore they can not understand the significance of their actions and to direct them. As a consequence of such citizens by the court established guardianship. Guardians of the law are members of the Trust and commit on their behalf and on their behalf all the necessary transaction. The trustees agree to commit those transactions that citizens who are in custody, shall not perform alone, in particular, any transaction with the property: sell, give, devise, exchange, buy. On the basis of Art. 37 CC guardian, trustee, their spouses and close relatives have no right to make transactions with the ward, also has no right to represent him at the conclusion of transactions or the conduct of litigation. Transactions in which a party is mentally ill, but not recognized in court as incapable, in particular the elderly with certain degrees of mental failure, alcoholics, carried out without a psychiatric examination. Article 43 of the Fundamentals of RF legislation on notaries found: "The identity of transactions it appears capable citizens and checked the legal capacity of legal persons involved in the transactions. In case the transaction is checked and the representative of his authority." However, the law says nothing about the right to appoint a notary public examination and put the question to the expert: Can a citizen to understand the nature of his action, committed and understands the legal consequences of the transaction since the sale, will, exchange, donation can significantly worsen the housing situation of a citizen, that is cause of the criminal situation in the housing market. The largest number of bonded transactions occur with the citizens who are not recognized by the court as incapable or incapacitated, but in fact may not be aware of memory. Before the court on the application of family members of the citizen, the trade union and other public organizations, public prosecutor, guardianship, mental health agencies may be asked to recognize a citizen partially incapable or incompetent. In this case the transaction by a citizen, later adjudged incompetent may be declared invalid by a court at the suit of his guardian, if it is proved that when the transaction was not a citizen able to understand the significance of his actions or control them.

2) Invalidity of transactions made by citizens, unable to understand the significance of their actions.
Law (st.177 CC) establishes that a transaction by a citizen, though capable, but are in the time of its commission in this state, when he could not understand the significance of their actions or control them, it is recognized by the court invalidate the claim that citizen or any other persons whose rights or legally protected interests violated by the transaction.
However, a transaction made in a state of intoxication, can not justify recognition of her invalid on st.177 GC due to a number of circumstances. First of all, in most cases the person is intoxicated is not completely loses control over its actions.

3) Invalidity of Transaction Concluded under the delusion that has significant value.
Quite a number of transactions involving the exchange of premises, committed under the influence of delusions, which are essential. The most common reason for termination of the transaction are hidden defects exchanged premises, sometimes unavoidable due to the design deficiencies house. In these cases, the transaction is declared invalid at the suit of the party who acted under the influence of delusion, while misleading the plaintiff and not the result of culpable other.

4) The invalidity of the transaction, done as a result of exceptional circumstances (st.179 GC).
To the court found invalid (bondage) bargain on this ground, it is necessary that the person challenging the deal, it was proved the existence of two features: exceptional circumstances and extreme bad deal.
Protection of housing rights of citizens under the age of majority. The law classifies minors citizens into two groups: those who are under 14 years old, and persons aged 14 to 18 years. According to Article 28 of the Civil Code for minors under 14 years (minors), the transaction can commit on behalf of parents, adoptive parents or guardians. . Minors aged 14 to 18 commit the transaction, except for small household, the written consent of their legal representatives - parents, adoptive parents or guardians. The deal, by such a minor, valid for its subsequent written approval of his parents, adoptive parents or guardian. Ability in this group of juveniles growing at the age of 16. A minor who has attained the age of 16, may be declared fully operational, if it works under an employment contract, including contract, or with the consent of parents, adoptive parents or guardian is engaged in entrepreneurial activities. For transactions in respect of privatized dwellings inhabited by minors, requires prior permission of the guardianship authorities. This rule also applies to residential premises in which minors are not live, but at the time of privatization had on it a dwelling equal rights with the owner.
Failure to observe this order transaction may be declared invalid. Each of the parties to the transaction to repay the other side of whatever is received in kind, if it is impossible to return in kind - to reimburse the cost of money.

Responsibility for illegal transactions with housing.
When the transaction through fraud for its participants come following the civil law implications (st.179 CC): If a transaction (a contract of sale of housing, gift, exchange, barter, etc.) will be recognized as invalid by the court, the victim returned to the other party All she had received in the transaction. If unable to return the dwelling in nature (for example, it was resold, and it spelled out, and live new tenants who have no alternative accommodation) the cost of the premises shall be compensated the victim for money.
In many cases, fraud is an act of criminal nature and, along with civil penalties entails the application of measures of criminal responsibility, which significantly strengthened in the new Criminal Code.
Thus, under the Criminal Code st.159 perpetrators of this crime, depending on its severity is punished by a fine, or compulsory or corrective labor or imprisonment for a term of four to six months, or imprisonment for up to ten years, with the possible confiscation of property.