The most you can have in your account is 999,999,999 bells. I think I had a bit more than 20 million in one my accounts in my old town, but now the highest I have on one character is around 8 million.
I buy cheap and sell high. I also made a lot of bells because when the game was still new I was one of the first people to start selling Gracie stuff in these forums so I made a lot that way. After that I just started buying as many rare items as I could and waiting until they went up in price to sell
It's not that difficult (you can sell certain villagers for like 45M, can easily turn 2M into 15M with turnips, can buy cheap and sell high) But I think it'd be pointless to get 999,999,999. You'll never need that much money.
I buy cheap and sell high. I also made a lot of bells because when the game was still new I was one of the first people to start selling Gracie stuff in these forums so I made a lot that way. After that I just started buying as many rare items as I could and waiting until they went up in price to sell
This was back in 2013 so idk what the prices are now like. But I used to buy 7-11 sets for 1M and auction them off in TBT. Sometimes they'd sell for like 30M :0