re: How do I build passive income?

I love threads like this as i'm thinking daily on how I can create additional revenue streams. I own a business and have a 5 figure sum sitting in a bank account that I want to do something with. I have thought of investing in a duplex as a first time real estate purchase, letting that materialize until I could build up capital to buy another duplex. Ultimately having the funds available to have several duplex's and then purchase a small apartment community after liquidating the duplex's. I've also thought about purchasing a FEDEX route or a bread truck route, but have read horror stories about those type of investments due to relying on someone else. There is so much opportunity out there that I haven't taken advantage of due to just not having time to complete my due diligence. I can't put the money into a Roth as I make too much money. I've thought about putting it into the stock market, but have a fear that the market is going to shrink faster than it's going to grow in the next year.

Threads like this give me ideas that I haven't thought of and perspective from other people. So, thank you to the MB for the replies. There's no quick way to earn cash flow right now so patience is your best friend.