Have you talked to a Salesforce rep? Seriously. They would be best and most knowledgeable to tell you whether their software can do what you want. Business-wise, your post frightens me with the impression of unbridled, "The customer wants it? Let's build it--who knows or cares if it's profitable...
I would start by looking at the apps and software you like to use that was created by smaller firms (not the big companies). Many of these firms also do client work, which you can find out about on their web site. If you enjoy the apps they produce and they have the expertise you are looking for,...