Directory Setup For Multi Client Yii Application

So I have my first Yii app ready in a few days from now. However, as a biz owner I see prospects of different clients wanting the same software but I do not want to have to maintain x copies of the same app for x number of clients. This will cripple my biz.

So I am trying to figure out a way to use same core for all clients and just create views only for clients. This wil be x set of views for x clients but easier that way. Problem is how do I do a directory structure so all clients share the same models and controllers. Of course, they will all run on my server much like a SaaS thing.

thanks for any help.