It depends on your personal needs. You can buy whatever you want. If you set a fixed investment, you must ensure that there is money in the card until the deduction date. You can buy the rest if you want. But many funds have quota restrictions. For example, some funds need 1 1,000 yuan, while others need 10 yuan, 1 1,000 yuan. The money fund seems to start at 100 yuan. So it depends. If you buy a fund, many funds have to charge a fee, and you have to charge a fee for redemption.