Italy Trip (Preparation)

I will have a 12-days Italy trip soon! This is my first time travel to Europe and i will go with one friend who I met almost a year. She is YM.

We planned to go four cities in Italy: Rome, Florence, Venice and Milan. Train ticket between cities and 12 days hotel are booked but we didn’t plan too much on the attractions as we know we cannot visit them all! Too much church and museum, and this is a leisure trip.

Few of my friend who visited Italy or heard about their friend travelling comment, are reminded me to beware of my belongings. I am concerning about this pick-pocket too, so I bought chains and lock to secure our luggage and bag. I am not going to bring my DSLR for the trip, it is heavy and i am afraid of someone will rob it. You can see how much I am concerning about my property.

I spent almost HKD $20,000 booking everything and now planning to buy a new digital camera for the trip instead. Still thinking which model should I get. 
These are put in my cart : 
1) Canon Gx7 markII
2) Sony RX100 III or IV
3) Ricoh GR II
4) Fujifilm X70

Fujifilm and Ricoh are are digital zoom while Canon and Sony are not. 
Price range from $4000~$6800. I am still thinking I should have one of these or just using my iphone 6 to take picture…