[@Seravee] Take a look at my attempt. I had a lot of great ideas. Feel free to use anything you see. Especially the class system. If you aren't doing the real life thing, then you can use the races too.

http://www.roleplayerguild.com/topics/86604-trapped-the-nightmare-begins/ooc

You've even got ideas for jobs there. 

There is an idea for a guild that I had in mind and the first floor that I thought up is there. I suggest you base your floors off other things, like the first floor on mine was going to be Olympus.