u/Local-Yesterday4020

I’m building a 3200sqft house in north alabama 1600sqft on each floor. My plan is to do a 2.5 ton mrcool ducted system for each floor. I would like someone to do a manual j to make sure that’s the right size units. I also can’t decide on the type of insulation I want to do spray foam so my utility bill is really low but I don’t know what the long term effects are. The units are variable speed so do I need a dehumidifier if so do I need one for each unit? Do I need an erv?