[Direct answer]In the Beijing area, there are four layers of risks: 1. **Taxation**: Declaring lower prices to evade taxes constitutes tax evasion. Those found guilty face tax recovery, late payment penalties, and fines. Both buyers and sellers are held accountable in the liability chain. 2. **Contracts**: Tax-avoidance clauses in contracts are invalid, but do not affect the overall contract. In disputes, settlements are based on the actual transaction price. 3. **Transaction security**: Buyers face moral risks (no proof of the price difference) when only recognizing the online signing price. Loan amounts are reduced due to the lower online signing price. 4. **Resale**: The low purchase price leads to a higher tax base for future sales. In short, saving a little tax now may lead to a series of future problems.

I. Problem Background and Typical Scenarios

The unspoken rule in second-hand housing transactions: the actual transaction price is 6 million yuan, but the online signing price is listed as 4 million yuan, and the difference of 2 million yuan is transferred privately—the seller pays less value-added tax and personal income tax, and the buyer pays less stamp duty. The agent says, "Everyone does it this way." However, when three types of people come knocking—tax inspectors, buyers who change their minds, and subsequent buyers who miscalculate taxes—the cost of this unspoken rule begins to become apparent.

II. Key points of dispute

First, the determination of the validity of the "yin-yang contracts". Second, the allocation of responsibilities and penalties for tax evasion. Third, the payment risk of the difference in price. Fourth, the chain impact of loans and resales.

III. Professional analysis by Henglue Lawyers

First Level: Contract Effectiveness: The online signing price and the actual price coexist in the contract. The tax-avoidance price clauses are invalid due to malicious collusion harming the state's tax revenue interests, but the overall effectiveness of the sales contract is not affected - judicial practice determines the price and settlement based on the actual transaction price, and the penalty for breach of contract and compensation for price differences are also calculated based on the actual price. The defense of "using the online signing price as the basis" is not supported, and any benefits gained from tax avoidance at a low price cannot be obtained at the contract level. Second Level: Tax Liability: The characterization of tax underpayment - taxpayers who adopt deception and concealment methods to make false tax declarations to evade tax payments are subject to tax evasion (tax evasion), and tax authorities can recover taxes, late payment penalties, and fines (50% to 5 times the amount of unpaid or underpaid taxes). Both parties have the obligation to make up for the arrears, and the late payment penalties are calculated at 0.05% per day, with the amount increasing over time. Criminal risks - if the amount of tax evasion is large and accounts for more than 10% of the tax payable, it may constitute tax evasion. After the tax authorities issue a recovery notice, taxpayers who make up for the arrears, pay the late payment penalties, and accept administrative penalties may be exempt from criminal prosecution (the first violation is forgiven only once). After the interconnection of the Golden Tax System and real estate registration data, transactions with prices significantly lower than the appraised price will automatically trigger alerts. Third Level: Payment Risks: The characteristics of private transfer of the difference in payment are "without a contract basis" - if the buyer repudiates the claim that only the online signing price is owed, the seller must rely on chat records, audio recordings, and fund transaction records to restore the actual price, with the burden of proof falling on the seller. Cash payment of the difference is even more difficult to prove. Conversely, the buyer is also afraid - if the seller claims the price difference based on the actual price, or demands tax supplementation after tax verification, the cost will be passed on and disputes will continue. Writing the actual price into the supplementary agreement to avoid taxes is equivalent to handing oneself a knife. Fourth Level: Cascade Effects: Loans - the online signing price directly reduces the mortgage loanable amount (loan ratio multiplied by the online signing price), and the down payment is passively raised; resale - the tax is calculated based on the lowered cost price, and the deduction base for future sales of value-added tax and personal income tax will be lower, shifting the tax burden; demolition compensation - the lowering of the price may reduce the compensation base; donation and inheritance - all links related to the registration price are affected. Fifth Level: Compliance Alternatives: Pre-tax calculation of fees (fully utilizing legal tax-saving spaces such as "five-year single ownership" and "family housing quota" first); clearly defining the price and tax burden clauses in the contract (each party bears the responsibility according to law or the effectiveness of the tax-inclusive clause); and seeking professional advice for large-scale tax compliance review of transactions - the money saved through legal planning is clean, while the money saved through tax evasion comes with interest and fines.

IV. Practical suggestions and legal basis

The first step is to avoid underreporting: declare the price truthfully, and handle cases where the appraised value deviates from the actual value in accordance with the verification guidelines. The second step is to take advantage of policies: plan ahead for legal exemptions such as the "five-year rule" and unit count verification. The third step is to maintain the true price: ensure the contract and transfer receipts reflect the actual price to eliminate verbal price discrepancies. The fourth step is to conduct thorough checks: prioritize tax calculation and contract review for large-scale transactions. Main legal basis: Article 63 of the Tax Administration Law of the People's Republic of China, Articles 153, 154 of the Civil Code of the People's Republic of China, and relevant rules of the Interpretation of the Supreme People's Court on Several Issues Concerning the Application of Law in the Trials of Disputes over Commodity Housing Sales Contracts; specific application shall be subject to the currently effective regulations.

5. Henglu Law Firm's Advice

Three key points to avoid tax evasion during online signing: Setting a low price is tax evasion, and you'll still have to pay back arrears and fines; Tax-avoidance clauses are invalid and the actual price will be used for taxation; Legal tax savings depend on policy flexibility, and it's safest to calculate prices, taxes, and fees in advance. For matters related to second-hand housing transactions and tax compliance, you can consult a professional.Real estate transactions and construction projectsWe provide a comprehensive solution for services, which includes strategies for dealing with tax-related disputes\nFinancial capital and cross-border transactions involving foreign entitiesFor plates, those involving the review of transaction contracts can be referred to for referenceBusiness and contract disputes in enterprisesFor reference, you can refer to the sections related to the drafting of transaction documentsSpecialised legal services板块。

VI. Frequently Asked Questions

Q1: What will happen if tax evasion through "yin-yang contracts" is confirmed?

The tax authorities will recover the overdue taxes and impose a fine of 50% to 5 times the amount of the overdue taxes; if the amount is large and the proportion meets the standard, the taxpayer may be suspected of tax evasion. After making up for the tax arrears, the taxpayer may be exempted from criminal punishment for the first offense.

Q2: Does setting a low online signing price affect the loan application?

The impact. The mortgage amount is calculated by multiplying the online signing price by the loan-to-value ratio. After the price is lowered, the amount of loanable funds will decrease, and the down payment will increase passively.

Q3: What should I do if the buyer refuses to acknowledge the difference in payment?

The seller uses chat records, audio recordings, and bank transaction records to reconstruct the actual price. It's almost impossible to provide evidence of the cash payment difference, so it's better not to conduct cash transactions.

Q4: If the tax avoidance clause in a contract is invalid, is the contract still valid?

The contract is valid in its entirety, but the tax-avoidance pricing arrangement is invalid. The payment and breach of contract liability shall be settled according to the actual transaction price.

Q5: Is there any room for legally reducing taxes?

Yes. Policies such as the "only-once rule for property purchases", the determination of the number of family-owned houses, the standard for ordinary housing, and the reasonable valuation range provide policy space, ensuring that pre-planning is legal and compliant.

The above content is based on the judicial practice in the Beijing area. The facts of individual cases and the jurisdiction of the court may affect the conclusions. Welcome to consult Henglue Law Firm for specific cases.

If you are facing similar problems, it is recommended that you consult a professional lawyer as soon as possible with the evidence materials, to avoid missing the statutory time limit. →Legal services for the purchase and sale of real estate·Beijing Henglue Law Firm

Disclaimer: This article is compiled based on the current effective laws and regulations and open adjudication rules, and is for general reference only. It does not constitute a formal legal opinion on specific cases. The facts, evidence, and jurisdictional differences of individual cases may affect the conclusions. In case of disputes, please consult a practicing lawyer in time.