I tried to reach Giovanni a couple of times before the trip to ask for the details of check-in, but did not get an answer. He then sent us the time when we were already on the road, via the app. When we didn't reply until 40 minutes before the meeting to say that we were already at the spot and looking forward to the meeting (little internet access + I thought, it was a fixed time), the time for check-in got pushed from 9.45 am to 3 pm, which was quite a big inconvenience. I tried to offer to pick up the key somewhere, but after the message that nobody was picking us up, there was - again - no reply until 3 pm. We probably should have replied earlier, however there seemed to be very little effort to reach us for a response and none after telling us that there wouldn't be anybody coming to the meeting point.
So just make sure you'll have internet access for the trip and check the app.
Apart from the first day however, we had a lovely stay at the apartment. It has a nice roomclimate, which was great in the summer (!), it's cosy, you can cook in the kitchen and it is very nicely situated at the end of a little alley. We really enjoyed staying here, in close proximity to "touristy" spots like the Rialto bridge, the canal and market, but also a bit of "real" Venice, since the immediatly surrounding streets were quiet or otherwise populated with market workers who were storing their goods.
Proximity to the Rialto bridge is also great if you like to walk, since it connects San Polo to San Marco and the east of Venice.