Visiting from London we stayed for 3 nights and really enjoyed our time in Cosimo's place. The location really couldn't be any better. It's about 30 seconds from the centre by foot, yet still quiet at night.
The place though small is good for a short stay in Ostuni. The sofa bed may not be for everyone but it suited us given we spent most of the time out and about. Parking is free although it needs a little bit of patience and careful checking of signs to find a free space. We just asked a few locals and it seemed fine.
Cosimo gave us a quick tour of the town and showed us a great fish restaurant and cafe.
The sun terrace is beautiful and a nice place to enjoy with the sun setting in the evening.