Waco-area residents could see homeownership costs rise if McLennan County approves a property tax increase, even though the City of Waco plans no change to its own rate. For the median homeowner in Waco, figures cited by KXXV amount to roughly $90 more per year overall. What's happening? McLennan County is considering a 6-cent increase in its property tax rate, while Waco would leave its rate unchanged. For a Waco home with a median value of $27…