Periods: ad valorem taxes use the calendar year of the closing date (Jan 1 to Dec 31). Non-ad valorem assessments default to Oct 1 to Sep 30; use the Period dropdown to switch to Jan 1 to Dec 31, or choose Custom dates for a district on a different year.
Paid through (taxes): enter only the year. The month and day are set by the Period: 12/31 for a calendar year, 09/30 for Oct 1 to Sep 30, or the end date of a custom period. The year is whatever the seller has actually paid through, so check the bills. Seller-paid days after closing are credited to the seller; days the seller owned but has not paid are credited to the buyer. Required.
HOA / Condo: choose Monthly, Quarterly, or Annually and enter the date dues are paid through. Paid through is required. It is treated as the last day of a billing period, and the billing cycle is worked out from it and the frequency (quarterly paid through 12/31 means periods of Oct to Dec, Jan to Mar, and so on). If the association is behind (paid through earlier than closing), the seller owes the buyer for every unpaid day up to closing. If dues are prepaid beyond closing, the buyer reimburses the seller for every prepaid day after closing, including whole future periods. Use "+ Add an association" for each one; none are shown to start.
Ad valorem: bills issue in November and are delinquent after March 31. Use the actual bill when issued; before then, the prior year's bill or an estimate. To apply the 4% early-payment discount (bills paid in November), check the box in the Property Taxes section. It applies to both lines, your entry stays as typed, and the Amount used column shows the discounted figure that the proration runs on. If you enter the net amount actually paid, leave the box unchecked. Day count: actual calendar days, not 30/360. Not included: capital contributions, transfer/resale fees, reserves, escrow balances, prepaid items.