To be very blunt and get right to the point, everyone is at risk of being home invaded. You can only begin to imagine the ways in which the bad guys operate. One should never feel so secure, even in their own home, that they drop down their guard. A person may have a whole safe full of guns and never get to use one. Here are a few good tips. Please feel free to add your own:
http://www.psp.pa.gov/public-safety/Documents/PSP_Preventing_Home_Invasions_Pamphlet.pdf
http://www.psp.pa.gov/public-safety/Documents/PSP_Preventing_Home_Invasions_Pamphlet.pdf