There is no difference between the two. One-time purchase is aimed at existing funds, that is, you have some spare money that you can't use in the short term. This money is suitable for one-time purchase. Fixed investment is aimed at incremental funds, which is the money you will earn in the future. According to the rhythm of income, you will make regular fixed investment. For example, Guotai Juxin A Fund, which is sold by Ding Xin Huijin APP, was established on 20 13 12 17 with a net value of 1 yuan. As of 2020 10 2 1, the cumulative net value is 3.549 yuan, and the cumulative rate of return. If you have 654.38+10,000 yuan of spare money to buy at one time during the fundraising period, the current asset market value is 354,900 yuan. If you didn't have spare money at that time, but decided to invest 1 1,000 yuan in this fund on the 5th of each month, and calculate by reinvesting in dividends, then up to now, you have invested 82 times, with a total investment cost of 82,000 yuan. Up to now, the total assets of the account is 204,782.20 yuan, and the rate of return on fixed investment reaches 65,438+049.73%. Comparing the cumulative rate of return of 368.86% with the fixed investment rate of 149.73%, the fixed investment rate of return is not as high as the cumulative rate of return, which is also because the efficiency of capital use of fixed investment is not as high as that of one-time purchase. Therefore, it is recommended to buy idle money at one time and hold it for a long time, and the incremental funds are recommended to be fixed.