In terms of price per unit output of energy, propane costs are higher than other forms of energy such as natural gas and even electricity. It depends on the price at which you acquire your supply of propane.
Some suppliers can offer it at a cheap discount, but in general, propane costs are higher.
It is important to know how to properly handle propane as it can be very dangerous and has the ability to explode to catastrophic levels. Carbon monoxide poisoning is also possible as a result of incomplete gas combustion of propane.
In fact, 25 percent of propane related fatalities are due to carbon monoxide poisoning, making it important to have a properly functioning propane appliance in your home. If tanks are allowed to go empty they may also corrode and oxidize.
Propane heating may not work in very low temperatures. If the temperature reaches below -29 degrees Fahrenheit, the liquid in the tank may not turn into gas and combustion may not occur -- causing your heating appliance to be unable to produce heat.