1）房屋保险，是不是要和保险说，把目前的保险改出另一种出租保险？两者有大区别吗？Yes, call your insurance comany to switch, no big change on cost
2）听说有一种保险，买了以后，如果租客发现房屋里的东西有问题，可以直接打电话，就有人来修了，这种保险叫什么险呢？
it is not insurance. It is called home warranty company. good search for it. normally 500-600/year primium. and $60 deductable per case. if your house is old, then you should buy it. otherwise, no need
3）如果确定租客后，是不是要把我们名下的水、电关了，让他们自己开水、电、煤气帐户？Yes. You need to do this. if the tenant do not pay gas or electricity, the gas or electricity company will go for tenant for it. However, since water is normally opeated by the city, it is your responsibility to pay if the tenant do not pay. So, make sure you check once in a while to make sure they make payment.
4）还有些什么需要注意的呢？Find a good tenant is key. If you have eisiting handyman/contractor, maintain good relationship wiht them for future repairs. you can also find contractor from angie's list
