For the purposes of this article, the following words and phrases shall have the meanings respectively ascribed to them by this section:
The word "dwelling," as used herein, shall be defined as a home constructed upon real estate owned by the qualified property owner or a manufactured home, as defined in § 36-85.3 of the Code of Virginia, 1950, as amended.
A person is permanently and totally disabled if he is so certified as required below and is found by the Town Treasurer to be unable to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment or deformity which can be expected to result in death or can be expected to last for the duration of such person's life.