So what are some good ways of making bells? I've relied on the non-native fruit forests that got me through Wild World. Are there any new systems? I've heard something about beetles too, but all mine are quite cheap!
I've spent most every day fishing. In your town, spend an hour or so and release anything that doesn't get you min. 1000 Bells at Re-tail.
Once you've got access to the island, spend time there, fill up the transfer basket, with sharks and huge fish. Get to know which fish will bring in 10,000 each. Go there after 5pm for best chance of getting the big catches.
I've been doing this most days and have gained myself about 200,000 per day. I've banked it and managed to pay off all the debts to Nook, currently have the 498,000 mortgage going.
With some patience you can rack up loads of Bells with a little bit of effort.