I actually ended up renting a mobile hotspot from xcom global. It was so convenient to have one, it came in handy when we weren't near any hotels or cafes and needed to look at Google maps.
The size of the hotspot was small enough to fit in a pocket or purse and we only turned it on when necessary because battery life was only about 4 hours.
The process was easy - create an account, your dates of travel and they send you the hotspot a day before your trip. They also include a self addressed envelope for you to ship it back.
I will definitely use them again on my next trip to Europe.