1. There are free buses called CAT buses that go on different loops round the city. You just hail them and get on (no ticket needed). There is also a big bus tour which obviously comes with a cost but you get the commentary. As often with those buses the cost for 48hours is not double 24hours, in this case just a few dollars more.
2. The Bell Tower is not open on on a Monday or Tuesday. So I know from outside it is a tall glass building with water in front and lots of padlocks on chains next to the water.
3. You can pay for boat to Rottonest Island. 🐀 🏝 Apparently people tend to spend about 5hours there! The main attraction is quokas which are marsupials but look like rats 🐀 hence Rotto in island name. But you can also see quokas in the zoo in south Perth.