I've done it - but not sure I can remember how! He needs to link a personal page to the business page by making himself an administrator. I think when you are setting up the business page you get the option to choose 'business' rather than 'person'. I think he also needs to like the page too.
When you have got that far pm me and I will see if I can find my notes on doing the rest of it.
My BIL has asked me to maintain a page for his business and advertise an upcoming event on other relevant group pages. However, it doesn't appear to be possible to join the groups when I'm using fb as the page itself. I don't want to join the groups as him because he doesn't do fb at all and only has an account so that he can have a business page and his account is in a made up name.
The only options I can think of would be to change his account name to that of the business, or to join as me and link in his page that way.
Is there another way? Does any of it make any sense?!