The Venice Airbnb was in a great location, the host made it very easy for us to find the place as they met us at the boat taxi stop and walked us over. We had 4 apartments in the building, two with 2 bedrooms (3 beds), a pull out couch, and 1.5 bath and 2 with 1 bedroom (1 bed), 1 pull out couch and one bath. The apartments were on the 2nd and 3rd floor and there is no elevator in the building.
In Florence we had 3 apartments but they were not all in the same building and we were not told this ahead of time. Two were right next to each other and the 3rd was a 10 min drive. The two together were 5 min walk from the train station and the 3rd was a 5-10min walk to the Duomo. Both locations were great and luckily for us part of the group being further away wasn't a huge problem but it would of been nice to know this ahead of time. The apartments were on the 3rd floor with no elevator.
The Rome Airbnb's location was amazing: it was right in the middle of the square, a short walk from the train station and had plenty of restaurants and stores at its doorstep. There were 5 bedrooms in total with great views from 4 and had 3.5 bathrooms. The host provided breakfast items which was great to start off without having run to the grocery store immediately. The downfall to this place was it definitely wasn't big enough for 15 people like advertised. Four of the bedrooms had a queen sized bed and then they added a cot and one bedroom had a queen size bed and a pull out couch. This place should of been for 12 people max. It was on the 5th or 6th floor and although extremely tiny, it did have an elevator which was a Godsend after Venice and Florence.