Advice: Know the laws of your state and use your resouces accordingly. Also, those wireless webcams are fairly cheap and can log to a hard-drive where the files could be deleted every few days or so. The DCS-900 is ony around $100 or so.
The camera + a dog + a Ruger could give one some pretty good peace of mind.
Following is an example of Arizona State Law
13-407. Justification; use of physical force in defense of premises
A. A person or his agent in lawful possession or control of premises is justified in threatening to use deadly physical force or in threatening or using physical force against another when and to the extent that a reasonable person would believe it immediately necessary to prevent or terminate the commission or attempted commission of a criminal trespass by the other person in or upon the premises.
B. A person may use deadly physical force under subsection A only in the defense of himself or third persons as described in sections 13-405 and 13-406.
C. In this section, "premises" means any real property and any structure, movable or immovable, permanent or temporary, adapted for both human residence and lodging whether occupied or not.
13-408. Justification; use of physical force in defense of property
A person is justified in using physical force against another when and to the extent that a reasonable person would believe it necessary to prevent what a reasonable person would believe is an attempt or commission by the other person of theft or criminal damage involving tangible movable property under his possession or control, but such person may use deadly physical force under these circumstances as provided in sections 13-405, 13-406 and 13-411.
13-411. Justification; use of force in crime prevention
A. A person is justified in threatening or using both physical force and deadly physical force against another if and to the extent the person reasonably believes that physical force or deadly physical force is immediately necessary to prevent the other's commission of arson of an occupied structure under section 13-1704, burglary in the second or first degree under section 13-1507 or 13-1508, kidnapping under section 13-1304, manslaughter under section 13-1103, second or first degree murder under section 13-1104 or 13-1105, sexual conduct with a minor under section 13-1405, sexual assault under section 13-1406, child molestation under section 13-1410, armed robbery under section 13-1904, or aggravated assault under section 13-1204, subsection A, paragraphs 1 and 2.
B. There is no duty to retreat before threatening or using deadly physical force justified by subsection A of this section.
C. A person is presumed to be acting reasonably for the purposes of this section if he is acting to prevent the commission of any of the offenses listed in subsection A of this section.