WP 8.1 C# - Instantiating a class and using its methods & properties

I'm developing a WP8.1 app & in this app I have multiple site (currently 18) that I fetch some data from them & each site has a hub page in app.

Those sites classes has same methods & properties and the only difference between them is db query and body of some methods.

What I'm going to do is to dynamically instantiate those classes and use properties or call methods because those sites can be disabled by user, and enabling/disabling performed with saving name of classes in db.

It's good to say that I've searched a lot for this purpose & what I get couldn't help me and lead me to the way