According to your and your wife's monthly income 1w, the monthly net income can reach 9000 if you spend about 300 yuan, plus insurance (about 420 yuan per month) and other expenses.
On the other hand, according to the total annual expenditure of your two children from primary school to senior three is 20,000 yuan, and you deposit 5,000 yuan in the bank every year with an interest rate of 3.5%. From primary school to university graduation (16), you need to have 65,433 yuan in the "education fund" for your children (that is, all the money in this passbook is used for children's schooling). With this account, if there are no other large expenses (such as children going abroad), your children's education expenses should not be a problem.
In this way, your disposable time deposit is about 20,000 yuan, and the net income minus the money saved for children every year is about 9000-(5000/ 12)= 8600 yuan per month.
In this way, it should be no problem for you to buy a car around 10w within one year.
In the future, it is no problem to spend an average of 3000 yuan for the elderly every month.
This is only a general assumption, and you can modify it according to this standard and your actual situation. For example, the risks you can take, such as the education funds you save for your children, can also be used for long-term investment (fixed investment or something) if you like.
Besides, do you only spend about 300 yuan a month? Is this yours alone or yours?