I love the way you phrased your question.
Not only does it have to be the cheapest, but it has to be the "most cheapest."
I read this really as a question of saving both time and money.
The cheapest method to start a blog is going to be very different from the most cheapest method to start a blog that actually makes money.
Let's be clear.
Thanks to AI, it's so easy to create a blog nowadays.
You have to have the right tools.
You need an SEO tool to find the keywords in your niche.
You need to have a virtual assistant to find the top websites in your niche and reverse-engineer their keywords.
You need AI tools to generate content.
And if you put all of this together and you have an auto-publishing system spitting content onto your WordPress blog, you're good to go.
That is the most cheapest method to start a blog.
It's not a completely unintelligent or ill-advised way to start one because you're saving a lot of time, you're saving a lot of money, and there's a good chance that you will get traffic because this is based on SEO research.
Remember, you filter these through an SEO keyword tool, and you have a virtual assistant that makes judgment calls as to which keywords to target and which articles that trigger the keyword to replicate with AI.
So far so good, right?
Here's the problem: Google has cracked down on AI.
The most cheapest method isn't going to be as cheap as before, but the inputs are absolutely necessary.
I'm talking about having flesh-and-blood human beings edit your content so the facts are correct and most importantly, present the content in an engaging way.
This can mean rewriting headings.
This can mean rewriting certain bits and pieces to make sure that the content all flows into each other.
This way, when you're clicking deeper and deeper into the guts of a website, the stuff that you read before gets you excited about the stuff that you're reading now, which then has a natural relationship in terms of themes and contexts with the stuff that you've read before.
I've just laid out the internal linking strategy of your site, and if you pull this off well, there might be enough user engagement on your site for your blog to maximize the value of whatever traffic Google sends it.
That's how you make money.
You don't make money when you spend close to zero coming up with a massive site with lots of articles.
Anybody with the right tools can do that, and being able to do this alone doesn't guarantee that you'll be making money.
What would increase your chances of earning solid revenue with your website is when you make sure that the content you offer, no matter how you generate it, actually delivers the experience that your readers expect.