1. Become a hybrid flower breeder- People pay big for a ton of gold roses. (plus if you have no buyers nook will take Blue and golden roses for 2500 a pop)
2. Fishinz timez- Go fishing with all your pocket spots open holding your rod. You can usually make around 10k a run if you throw back all the cheap fish.
3. Hit rocks daily- If you have a silver or golden shovel find the money rock and smack away. you can get a max of 8,100b out of a rock and money rocks spawn once per day so its an easy 56k a week.
4. Rare furniture- Its winter. so roll up some snowmen and sell the furniture he gives you to nook, most pieces fetch around 10k.
5. Stalk Market- play the stalk market by buying around 900 white turnips from Joan on sundays (6am-noon) Wait for nook to offer at least 50 bells above what you bought them for and you will make 45k instantly. ((PROTIP: sell on saturday no matter what the price or else your turnips will spoil.))
6. Stalk Market Part dos- wake up early and buy the Red Turnip seed from joan. Bury it somewhere you know you will see it every day (outside your house works great) Water it everyday until next sunday and then sell it. The seed cost 1,000b - it sells for 16,000 -15k profit for minimal work.
7. Oysters. Pick up all the shells on the beach. If you find a Pearl Oyster they sell for like 2k i think.
8. Shake some trees- yeah, shake every tree in town that doesnt have fruit. You will make about 4k in 100b bags that fall from the trees and if your good (and lucky) catch the Bees that fall from trees, They sell for 4.5k
9. Talk to neighbors- They sometimes ask for chores or will buy items off you. This is a really slow way to make bells but if your desperate...
10. Visit towns- This is always a good choice. Visit a friends town with 15 of your own towns fruit in your pockets. Then sell your fruit in their town and BOOM 7.5k (make sure you and your friend dont have the same fruit though.) Then pick up a few of his/her fruit and either plant them as trees in your town or just sell them in your town for another 7.5k
Hope these give you some money ideas....Thats all i got.