There seems to be no shortage of contractors that sell and install new HVAC systems in GTA.  The problem is that a good number of the contractors do not have the after sale service/support capability.  Probably a good practice is to make sure the contractor that you select has a physical presence in your area rather then operating from a basement or the back of a truck. Apart from the product that you select it is also important to have quality installation. You can purchase the best product but if its not installed correctly and serviced you will not reap the benefits of energy conservation, the air quality or  the comfort a new system offers. Your interests are best served by choosing a reputable dealer/contractor that can and will service the product for an extended period.  Choose carefully and don’t let price in isolation drive your decision on a big investment.