Reading Opps Daily, a rather nice newsletter where people share their problems that can become business ideas, I was often mumbling to myself: "Hey! That already exists!"
And that's because a lot of business problems can be solved by gathering requirements properly, procuring a SaaS or installed solution, and just customizing it. The last step is sometimes optional. You can run a whole consulting business with two skills: listening to users and searching the web.
A lot of vendors give kickbacks for referring customers. You might be able to build a sustainable business by becoming very good at setting up one or two solutions if you are brilliant at finding businesses with a particular problem.