1. I can show the location of the zoning dampers... and depending on
how involved you want to get with premium service options, duct layout and sizing etc.
2. Energy savings is the primary benefit with zoning. Depending on which
option you choose the size of the equipment can be a bit smaller with
a zoned system.
3. The company only allows direct contact with phone and email if the
customer pays for at least one premium service.
4. I prefer the various non modulating systems. Both first cost and
repair costs are reduced that way. Modulating is quieter, however.
5. In your case it is most likely you will end up preferring, two smaller
zoned systems. allowing you back up when one of the inevitably fails,
and more fine tuning of the load saving maybe as much as 50% on
utility costs, and being much easier to diagnose and repair.
Goodman is very decent equipment in my view, the dealers though
do not have to meet franchise requirements, so the install quality can
be a problem unless the dealer is properly vetted. There are many
other options as well.
Let me know, we can go from there.