Marcos is an outstanding birder who is fluent in English. We got a full day tour outside of Cortona in Tuscany.  My wife and are beginner birders and Marcos did a terrific job spotting, getting us a look at,  and naming birds.  He is also very sociable and pleasant to be with.  He took us down to Lake Trasimeno and then up in the hills surrounding Cortona.  Birds galore and a couple of historic churches we would never found.  Bottomline we would definitely use Marco again and I personally hope to.