Correct me if I'm wrong but ACNL is probably the game in the series where you need the most bells. There are many more things to spend bells on like PWP and house renovations that are greater than other games. So what do you do to get tons of bells? Do you try the stalk market? There are the island beetles, although that can get repetitive really quickly. Another neat way is fishing in your own town or going deep sea diving. Of course, that's not as much as the island beetles but you can do them any time.
For me personally, I don't really like the beetles just because it's so boring and I can't do much unless I time travel, since I'm an early bird kind've guy (although the beetles are still around in the early morning). I haven't used the stalk market in a while, mainly because I'm afraid I can't play consistently enough to actually use it well. But fishing is always pretty nice, I can get some quick bells from there.
For me personally, I don't really like the beetles just because it's so boring and I can't do much unless I time travel, since I'm an early bird kind've guy (although the beetles are still around in the early morning). I haven't used the stalk market in a while, mainly because I'm afraid I can't play consistently enough to actually use it well. But fishing is always pretty nice, I can get some quick bells from there.