If an existing structure was built and does not meet the current development standards (such as setback or accessory structure location regulations) in the Zoning Ordinance, it may be permitted to remain if it is determined to meet the vesting requirements pursuant to § 15.2-2307 of the Code of Virginia. The structure may be permitted to remain if (i) the local government has issued a building permit, the structure was constructed in accordance with the building permit, and a certificate of occupancy (RUP or NonRUP) or a final inspection approved, or (ii) the owner of the property has paid taxes on the specific structure for more than 15 years, it is legal and can remain. If there is no evidence that a building permit was ever issued for the structure, building permit approval for the structure may be required.