This is such a geographically specific subject that it is impossible for me to write a comprehensive post on shelter. What I can say is that it is imperative that you research the hazards for the area you live in. Is it tornadoes, hurricanes, flooding, earthquakes or a combination?
Hopefully, you checked with your local Emergency Management Office before you bought your property. They can tell you if a certain area floods regularly or is vulnerable to other problems. In more rural areas the local fire department and police departments can fill you in. The federal government and local universities may be collecting data for your area. Take the time to do your research before committing to a location.
Once you've found the safest place to live in your area it is time to look at emergency shelters or construction techniques that can keep your family safe during emergencies.
In tornado prone areas a storm shelter should be a priority for you. Some shelters are pre made and delivered to your home ready to be sunk into the ground. Others are built in place. It is important that they be water proof, well ventilated and able to comfortably seat the correct number of people for your household.
A safe room within the home is appropriate for many problems. It can be used to protect your family from tornadoes, hurricane force winds, and intruders. These can be specially built into your house or you can choose a strongly built, windowless room in your house. I have two internal, concrete block, windowless, walk in closets in my house. What they need to be entirely secure is a strong door that can be locked from inside the closet.
When waiting out a long duration storm such as a tropical storm or hurricane it is imperative that your roof remain on the house. There are two main ways to ensure this: hurricane straps and storm shutters. The shutters protect the windows to prevent wind from blowing into the house, creating an updraft that weakens the roof. The straps physically hold the roof to the wall structure.
You can look into your attic to see if your home has hurricane straps. They are available for purchase at every home improvement store and are nailed into place. Super simple and effective.
There are many different types of storm shutters. I chose to have steel rails permanently attached to my masonry house. When a storm is approaching I use thumb screws to hold corrugated steel panels to the rails. I have a few panels that are a clear polycarbonate material to allow light into certain rooms. I can install these shutters onto the entire house, by myself, in half a day.
There are many other ways to provide safe shelter for your family. Take the time to do your research, prioritize, save the money and install these safety features. It can become more economical if you make them multifunctional. How about a safe room that is also a pantry?