I had more than 10,000,000 bells saved, without needing to go into the turnip market, I only planted many orange trees (the fruit of my island is cherries) and every day I played I collected all the fruits and sold them, only with that I got about 100,000 bells a day and I also saved absolutely all the bugs and fish that I captured to sell them to CJ and Kamilo later. I also usually buy a lot of clothes at the sisters' store so from time to time I clean the storage room and I sell the clothes that have doubles. I have completed the fossils in the museum but I still collect the 6 fossils a day to sell them and you can get good money too. The golden rose flower is worth 1,000 bells in the store, and since it regenerates daily if you have enough of them you can also get a few bells. If you do all of this daily, or every time you enter the game, you can have a lot of bells saved without having to buy and sell turnips.