The casual burglar carrying a crowbar is unlikely to be able to penetrate this type of safe. Good hinges are either hidden or arranged in such a way that even if they are cut off that security isn't compromised. At the low end of the range the weight is low enough that a homeowner might reasonably move in the safe and install it with the help of another person or two. Also one has to start to get concerned about the load bearing capability of the floor where the safe is to be installed. If, because of these considerations, the safe is installed in a basement then humidity becomes an important concern.
Common measures are silica absorption boxes or a simple low-wattage heater inside the safe.
Many safes are drilled for the electrical cord. There may also be features, such as a combination lock dial which locks into a fixed position with a key, which improve security. As the safe is improved in these ways, it becomes more and more resistant to burglars, until you reach the point that only the most skilled and well equipped burglars have a chance. As improvements are made, and as it becomes necessary for burglars to take a longer time, one can also shorten the time that they have by installing an alarm system. One inexpensive and elementary precaution is to hide the existence of the safe.