The only real similar question for this I discovered was this and also the answer recommended needing to use Reflector to discover.

How about in only a lot of the cases? Generally, may be the base method known as first or last inside a method?

I observed in certain libraries it's known as at the start in the method as well as in the XNA Framework they are known as in the finish of techniques (base.Update, base.Draw, etc).

It is dependent on whether you would like you derived behavior to occur before or following the base behavior.

Also keep in mind you are able to call the bottom method in the centre or otherwise whatsoever.

With that said, generally it will likely be known as because the first factor. Because then you definitely overridden method has the opportunity to 'overwrite' configurations made by the bottom-class.

However in techniques like Close or Dispose it's more customary (sometimes mandatory) to refer to it as ultimately.

It entirely is dependent on which for you to do. There's not just a "general" rule by what should happen. For instance, you might like to perform some extra validation, then call the bottom method, then make a move else. Or possibly you want to time how lengthy the bottom method takes to call.

Treat each situation being an individual situation.