Tax sale and redemption practitioners should note, as did the Court of Civil Appeals, that section 40-10-122(d) does not specify any particular manner of delivery of written demand for insurance premiums and improvements. Instead, any form of written communication—all written correspondence (whether handwritten or typed), electronic communications such as email, pleadings, motions, and most other types of communications--likely qualify as a “written demand” triggering the tax sale purchaser’s duty to respond and provide the amount claimed. More generally, though, because the right to seek reimbursement of insurance premiums, preservation improvements, and permanent improvements is statutory in nature, the practitioner must take extra care in complying with any deadlines or schedules contemplated by the redemption statute.