In one sentence:
Sell one editable website template many times to a business niche.
Businesses that are just starting need a logo, domain name, email address, social profiles and a website.
Out of these five things let’s focus on a website because we have a good solution for that.
Business that are just starting are short on money, time and website content because they haven’t done any business yet. So they need affordable, one page website template website quicky. I know, there are hundreds of ThemeForest WordPress universal templates with all possible page/feature combinations but small business do not have a time to compare and select, content to fill all these pages, and time to learn to maintain such ‘operating system’ kind of a template.
But, they can definitely manage a specialy customized one pager for their own niche. Especially if it’s coupled with a simple, drag and drop CMS 
So, what business niches are good for starting? Well, for example:
- general contracting
- landscaping
- house building
- house remodeling
- beauty salon
- nails
- hair salon
- spa
- massage
- yoga studio
- lawyer office
- accountant
- psychologist
…
At the end, this is not my original idea, this is something I saw that Sitecake white label users are already doing. For example these three agencies from US, Brazil and Russia.
