Should our estate have 2 Heating & A/C systems?

I have spoken to our estate’s Heating & A/C provider & they encouraged myself and others to get a third Heating & A/C system, but I’m concerned that they are more interested in profiting from a third Heating & A/C plan than they are about the efficiency of the estate

At our estate, the heating & cooling costs tend to be unquestionably expensive on a biweekly basis. Since I rent the estate out to host corporate events, anniversarys, parties, etc, and i don’t normally see these costs as an issue. During this global pandemic, our estate’s anticipated lucrative summer time has been short changed. I’m really going to take this time to invest in making the estate even better for after the election. (Let’s be honest, this global pandemic will loosen up after November 3rd, mark our words). In any case, Christmas is a tied up season for me. I have often considered adding a third Heating & A/C plan to the estate to make the heating & cooling more consistent throughout. I think this would also extend the life of our central heating & central cooling systems. I don’t suppose if anyone here has any input on adding a third Heating & A/C plan to a big estate, but if so I would be glad to hear your opinions. Also, should there be an Heating & A/C provider who knows more about this than I do, I would love to suppose your thoughts. I have spoken to our estate’s Heating & A/C provider & they encouraged myself and others to get a third Heating & A/C system, but I’m concerned that they are more interested in profiting from a third Heating & A/C plan than they are about the efficiency of the estate. Again, our biweekly heating & cooling costs are already high with this estate & I suppose that adding a third Heating & A/C plan will be luxurious. I don’t want to waste money on something that makes no difference however I am willing to pay to make the estate more comfortable. Please, let myself and others suppose your thoughts below.

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