Door to door salesman came to sell Zephyr Air Purifier. I paid $4000 for this unit. Was told a 25 year service contract was in place that included free service and air filter replacement each year. After almost two years I have not received a new filter. I contacted the representative twice and have now been told that the filters cost $90 plus the cost of shipping - which is not what was originally sold to me. I believe I was wrongfully mislead into buying this product.