What Percentage of Buyers Don't understand HOA Fees & Taxes VS. Price of Condo ?

Yesterday , no matter how I tried to explain that a $200/mo HOA fee could result in savings of $72,00 plus over a 20 year period than a $500 HOA fee and that should be considered when comparing prices of condominiums ,it had no effect on the buyer.She just reacted to the price as too high and that was that .So as I know  must other agents already know ,you really can not change a persons mind if they really don't understand the concept and no interest in trying to understand .I know many buyers understand that all costs of buying  a condo are very important and each one should be carefully considered ,but I wondering how many agents come accross buyers who are fixed on price and what were your experiences.What is your experience?