Hi there, I don't offer this service but have worked with clients to get them set up with the basics. Social Media isn't my 'thing' so I haven't invested the time and energy in learning Facebook as some of the other VAs here have. There are VAs who specialize in it and can work wonders with a business page.
It sounds to me like you're going to want to play with Facebook business pages before offering this as a service. That way you'll know how long it takes you to create a page (and truly, every page is different - some are very basic, some are very in-depth) and you'll have a better understanding of how it works.
As to the protocol FB has in place I don't think there's really a 'way around it' - but I have two business pages attached to two sep. personal accounts (i only use one personal account actively) and in both cases no one can see that these pages are connected to my personal account.
Again, working with the FB options, you'll learn a lot - there are settings you control for each business page related to who can post on the wall, etc.
As far as I can see from my own use of FB just about ANY type of business can benefit from a page.
Good luck