The legal route of “buying insurance for a family member first, then harming them” is completely blocked: you get zero money, and the perpetrator faces multiple charges including intentional homicide and insurance fraud

No cost at all.

Article 34 of the Insurance Law: a contract providing a payout upon death is invalid without the insured person’s consent and approval of the insured amount. The insured is the person covered. This restriction does not apply when parents insure their minor children. Article 39: the policyholder must obtain the insured person’s consent when designating a beneficiary. The policyholder pays for the insurance, and the beneficiary receives the money when the insured event occurs. Article 43 concerns deliberate harm. If the policyholder intentionally causes the insured person’s death, disability or illness, the insurer is not liable to pay benefits. If premiums have been paid for at least two years, the policy’s cash value is returned to other entitled persons. A beneficiary who intentionally causes the insured person’s death, disability or illness, or attempts to kill the insured, loses the right to benefits. Article 27, paragraph 2: if the policyholder or insured intentionally causes an insured event, the insurer may terminate the contract and is not liable to compensate or pay benefits; premiums are not refunded except as provided in Article 43. Article 1125 of the Civil Code: intentionally killing the person whose estate is to be inherited results in loss of inheritance rights. Article 198, paragraph 1, item 5 of the Criminal Law classifies a policyholder’s or beneficiary’s intentional causing of the insured person’s death, disability or illness to obtain insurance benefits by deception as insurance fraud. A relatively large amount carries up to 5 years’ imprisonment and a fine of 10,000–100,000 yuan; a huge amount carries 5–10 years; an especially huge amount carries at least 10 years. Paragraph 2: if that conduct also constitutes another crime, the rules for combined punishment for multiple crimes apply, meaning the crimes are considered together in sentencing. Article 232: intentional homicide carries the death penalty, life imprisonment or fixed-term imprisonment of at least ten years. An example is the case of Zhang Mousong in Xuancheng, Anhui. In the early hours of July 18, 2016, he drove into a pond and his wife drowned. Less than half a month earlier, he had taken out four policies on her, each for 1 million yuan. He was arrested on July 25. For the combined crimes of intentional homicide and insurance fraud, the court imposed a suspended death sentence and a fine of 50,000 yuan.

全国人大常委会 (2015 修正). 中华人民共和国保险法第二十七、三十四、三十九、四十三条. https://flk.npc.gov.cn/detail?id=2c909fdd678bf17901678bf7c4060811；全国人大 (2020). 中华人民共和国民法典第一千一百二十五条. https://flk.npc.gov.cn/detail?id=ff808081729d1efe01729d50b5c500bf；全国人大常委会. 中华人民共和国刑法（经刑法修正案十一修正的整合文本）第一百九十八条、第二百三十二条. https://flk.npc.gov.cn/detail?id=ff808181796a636a0179822a19640c92；安徽省人民检察院转载《法制日报》(2020-01-13). 杀妻骗保牵出案中案（安徽省人民检察院民事虚假诉讼监督典型案例）. http://www.ah.jcy.gov.cn/jczt/jjslhyqkjc/mtjj/202001/t20200113_2758841.shtml

The beneficiary of this item is oneself, avoiding the death penalty or life imprisonment. The casualties and judgments in the cases are taken from the original text of typical cases published by procuratorial organs; the main text does not include details beyond investigative methods. Insurance fraud that does not involve human life, such as fabricating accidents or exaggerating losses, is also a crime. Those who help testify are counted together; see Section 9, Item 21 (fabricating accidents and exaggerating losses to defraud claims). Buying insurance for family members is normal in itself; what must be prevented is the thought of "buying insurance before acting." Impulses to harm family members should be treated as emergencies; see Items 14 and 15 of this section (the thought arises by oneself, or someone nearby utters threats).