privacy: the easiest way to blur out some location specific objects in a video My customer sent me a video, where she wishes to hide all location specific objects. The video viewer should not recognize where the video was filmed.

To blur out the location specific object, a human must decide what is privacy related and what not (it can't be done by algorithm). I wish to select an object (some tiny and some 50% of the resolution) and then some "magic" happens that this object is blurred in hole video. I wish to blur out only small portions of the video, that the result is enjoyable for our viewers.

I search for a very easy solution. I am not a Professional Video guy. I use macOS Sierra, did some basic stuff with ffmpeg and QuicktTime player (Trimming). For me it's possible to buy an extra software for about 100$. I prefer a very simple way to do this.
You are going to need to use; preferably After Effects to do this. You could also do it in Premiere; but AE is the way to go, because you can use the tracking feature to auto follow objects; combined with a custom mask (with a blur filter applied). 

Other than that your options will be limited. 

I believe Adobe CC allows a 30 day free trial; and it's monthly in terms of cost, you could always try it and see if it suits your needs, and go from there).