bounties with 4 players earn you the most money. Make sure the bounties are brought kept alive
This website should help you with the collector role. https://jeanropke.github.io/RDR2CollectorsMap/ I suggest to mess around with it to become familiar. Using that will help you complete collector sets quicker, thus getting you money quicker. With that cash, you can invest in your other businesses (trader & moonshine) to gain a better income from those roles. Having a larger wagon helps you run more product at once, and creating a stronger moonshine will get you more cash per delivery.
Find some collector collections, you can make easily 200/300 out of one collection. If you find 3 or 4 collections you most likely hit the 1000, it will take some time tho