Well in general its hosting, but obviously it depends what they want it for, so they could be a business user wanted a large scale e-commerce site, or they could just be a personal user looking for a place to put a few photos.
What customers want?
Read the answer to the last question.
What is the average monthly payment a customer will be willing to pay ?
Depends what they want, business users may pay you thousands for a site and group of servers. A home user is probably only looking for a few $ a month.
Is there any percentages or statistics out there that have percentages etc , like what age , or the most common people who look for web hosting
I expect it varies greatly from teenagers wanting to stick up a simple site to the "older" group looking to host a more professional web site.
I think you need to narrow down your research a bit because those are very general questions and its impossible to provide a detailed answer.