Texas Local Government Code - LOC GOV'T § 214.232. Presumption of Vacancy

(1) all lawful residential, commercial, recreational, charitable, or construction activity at the building has ceased, or reasonably appears to have ceased, for more than 150 days; or

(2) the building contains more than three units, 75 percent or more of which have not been used lawfully, or reasonably appear not to have been used lawfully, for more than 150 days.