The place is located near the heart of Bari — everything is within a walking distance. You have a breakfast place just on the opposite side of the street (if you like Italian sweet breakfasts) and a panini joint just a half block away. Two supermarkets (one with bio products) and a local grocery store are all no further than a block.
The place itself is perfect for a traveling couple — a well thought-of kitchen, a bedroom in the attic (you have to climb up a steep ladder to get there so I wouldn't recommend it for small children), a nicely lit terrace. The apartment is not very sunny — which is a good thing if you plan to spend a summer there. The walls are thick, the air conditioning unit is maintaining the perfect temperature.
The thick walls come with a nuisance — no cell reception whatsoever. Wifi is also very slow, so you'll end up checking your email or Facebook on the terrace. But hey, it's a perfect excuse for not answering the calls from your boss when you're on vacation :)
Francesco, the host, is very welcoming. He is also very responsive, answers the messages almost instantaneously. I highly recommend this place as a base for your travels through Bari.