Here are a few general points to answer your forum post question(s)...
If you buy a firearm, revolver or semi-automatic, make 100% sure she can safely load, unload, fire, handle and/or field-strip/clean the firearm BEFORE she carrys it. If she can not do these basic functions DO NOT carry it. A high stress lethal force event is not the time to mess around.
I'd add that before she carrys a loaded firearm be fully aware of the law/use of force standards. Guns are not toys or props. If she can't use LETHAL FORCE she shouldn't carry a firearm. Get a C2 Taser, OC spray or a impact weapon.
A firearm is not a security system it's part of security system. She should also have a white-light(tactical flashlight), a small knife and/or a second weapon like a defense pen(Uzi, CRKT, Tuff-Writer, etc).
Have her carry factory made, high quality ammunition too, no hand loads or reloads. Her statements, actions, weapons, and/or training may be held under review by a prosecutor or criminal investigator after a event.
Also, know that the LE investigators or detectives are NOT on your side! They are there to uncover the truth or find out what took place. Don't panic or prattle on. Use your civil rights, stay silent & get a criminal defense atty.
DO NOT speak to the media either. Nearly everyday, I see local news items where people go on camera right after a use of force event then yak it up.
The media is not a sworn LE agency or public service. It's a private company trying to increase ratings or profits. Your rights, safety or well being is meaningless to them.
See these websites for help; www.nra.org www.gunvideo.com www.handgunlaw.us www.gunsamerica.com www.natchezss.com www.grafs.com www.midwayusa.com www.paladin-press.com www.uscav.com www.safariland.com www.usgalco.com www.gunlawguide.com