One thing I have learned through life is that the more your pay for something, the more you will get.
This goes triple when it comes to central heating and air conditioning system units.
When you pay less at a regular sale price, chances are you will be getting a central heating and air conditioning system that is not the very best and most likely will have a pretty bad SEER rating. This is why when you are shopping for a brand new and really up to date central heating and air conditioning system you will want to go for the best and just try to find one on sale. You never want to buy a cheap regular priced central heating and air conditioning system no matter what the HVAC brand is. Even if it is one of the most top of the line heating and air conditioning system brands, if it is priced cheap at regular price stay far away from it! I learned this many years ago when I bought a cheap central heating and air conditioning system and then was having to invest in another HVAC unit a year and a half later! That nearly made me go broke. But the second time I bought a top of the line, up to date and very expensive heating and cooling unit that happened to be on sale for 40 percent off. And that heat and a/c system lasted me almost 20 years as a heating and cooling system should. These were my findings and I stick by this rule to this very day!