With a business account, you’ll have access to Pinterest Analytics, as well as the ability to create “Rich Pins.” You can also pay Pinterest to promote your pins with a business account, but that’s definitely not necessary. We experimented with about $50 worth of promoted pins before figuring out we could make our pins go viral on our own, without the help of ads.
Notice that I avoided putting a specific dollar figure on the amount you can make from blogging. It will come down to your work ethic, your skills as a writer, your ability to generate targeted traffic, and plain old good luck. It’s a bit like baseball: everyone played it as a kid, only a small fraction make it to college ball, an even smaller number become professional, but only the cream of the crop makes it to the majors.
A blog itself isn't really a business—it's more of a platform for other income streams. Your content alone won't likely make you money. Instead, you'll have to get advertisers, sell services like consulting or speaking, use affiliate marketing to get a percentage of sales from links people click on your blog, or maybe offer products like ebooks or premium content to actually generate income. ProBlogger has an excellent post about these different ways you can make money.
If your niche doesn’t allow you to promote or build premium products (anything over around $100 per unit) then think about getting a solid mix of offerings and building it up over time. I remember Darren Rowse saying that initially Amazon Associates was a really small source of income but over the years it has really started to add up. Think eBooks, affiliates, consulting, books, etc. and you’re starting to build an income stream.