Sorry Dave but your response kinda cracked me up, particularly the fire extinguisher
The serious side to firearms is proper training and understanding what self protection is regarding both law and common sense.
When you have a weapon of any kind, you are only going to want to use it for stopping power against maiming, injury or death to you or another human. You aren't out to kill anyone, you just want to stop them if there is no way of escape.
Another issues is how likely an attacker will be able to get a firearm out of your hands and into theirs? If you haven't had full training classes, odds are the attacker will end up with your firearm in their hands, just not a situation you want to be in. They aren't as afraid as you are and have had time to build a good level of adrenaline whereas you haven't. The stories of how many times a person can be shot and still approach a victim are true, its the amount of adrenaline and possible drugs that make it difficult for law enforcement to stop someone from threatening approach.
The last factor is two fold: trailers and vehicles have little to no slowing effect on a bullet so one would have to be prepared any bullet is going to go through and possibly injure an innocent person nearby. The other is how well you like your hearing - an enclosed space such as a vehicle or trailer/MH is going to amplify the sound when a round is fired, many people have ruptured eardrums from that alone. One shot and you can't hear anything - another person screaming, sirens, or your attacker (if its dark you would want to be able to hear if an attacker has fled or is closer to you).
My own preference has been taking a course in the 80's offered by Massad Ayoob with a refresher course every 5 years by his early students and other Law Enforcement Officers. He has published quite a few books on the subject of gun ownership, various scenarios and general laws relating to firearms for the general population everyday person. Some of the legal material is outdated though it still has the basic foundation of deciding on a weapon for self defense, as he points out, one does not need a firearm but a good sense of their surroundings, quick exit and judgement of any perceived threatening situation. All those factors should be taken into account when deciding on a way of self preservation.