When you think of creating a business or a business line of the one you already have on the Internet, you automatically think of investing, and you are not wrong because you will need to invest, but think about where.
On the Internet there are things that are necessary and things that are not. Web hosting is not necessary for you to provide; so you will have time and money to focus on where you add value, on what differentiates you from the competition and makes you more competitive than them.
You may think that hosting is strategic for you, and you're probably right, but that doesn't mean that you have to provide it yourself, because you can outsource it as you do with many other things and it won't be detrimental to quality and it won't increase your costs.
In the case of applications, the advantages are even greater. For example, if SMEs started using Google Apps they would realize the gigantic savings they could find, as they would go from paying for: licenses, maintenance, disks and more computing power, to 50$ per employee per year. Docs (Google's Office in the cloud) covers the vast majority of the office needs we may have and frees us from many problems; so, again, it allows us to focus on where we add value.