The Bexar County Tax Office offers the option of paying your Property Taxes online with either a major credit card or an electronic check (eCheck). If you require documents for a Mortgage Assignment, click on Assignment Forms below.For CO-OP PAY-OFF, click on CO-OP Bank Forms below. A mortgage payoff letter can come in two forms. One form tells borrowers the remaining principal amount and interest they have to pay to close out the loan. A payoff request can be created and mailed for free. How long does it take to obtain a payoff? Acceptable forms of payment are cash, check, or money order. Under the Loan Information section, you will find a payoff request option that will take you to our payoff request form. Use SmartAsset's free Texas mortgage loan calculator to determine your monthly payments, including PMI, homeowners insurance, taxes, interest and more.