This is a great place to stay in Castello in Venice. Its easy to access by public transportation (vaparetto/waterbus) from the train station (line 2 to Lido) getting off a Giardini station. From the station you have a 5min walk up scenic little park which ends at a main street dotted with great restaurants and cafes. The place is down one of the side streets which is wide and well lit.
Note that the apartment is at the top of several flights of somewhat narrow stairs, but the climb is worth it. On check-in we met Tinto, Lucia's son, who oriented us with the place and gave us information about the area and check-out. Lucia was in contact with us the day of over WhatsApp and when we left as well; the owner is very responsive and is happy to help or guide you in the city.
The apartment is very large for the area; is kept immaculately clean and stocked for guests; has a wonderful little balcony and boasts an amazing view from the rooftop.
It is super close to the Arsenal (5 minutes) and The Doge's Palace/St.Marks (10 minutes). I happily recommend Nevodi restaurant which is on thee mainstreet near the place; however that is all because exploration is the best part Venice!
We would happily stay here again on a return trip to Venice!