From what I've seen, in my 15 years in tech and programming, this never works.
I have prior success in online marketing and sales such that I'm able to live permanently in the Philippines and other countries from my online income alone.I've identified a few niche dating sites that I know could turn a profit, however I lack the programming experience to write a custom CMS.Have a clear, list of features that you think you need to bring a product to market.Plan out all UI/UX elements and have a very specific sitemap and procedure map.You might learn from similar sites/competitors during doing this step. The sales/marketing is probably the easiest part especially with niche sites.
After that, you could looking for software development outsourcing providers or freelancers to deliver the rest. You could get a modified pre built CMS and probably be alright especially as an MVP.
Eventually, everyone gets fed up after it's clear that it will take hundreds of hours of programming work just to create a proof-of-concept, and people start dropping out.
Good, experienced developers are expensive and difficult to come by.
I'm sure that you have a lot of experience in marketing existing products, but building something from the ground up takes a different skillset that takes time and / or money to acquire.
My personal advice, learn some basic programming skills to get an idea of the complexity of what you want to build.
and if you don't like the people personally, don't settle, Best of luck!