"jay" wrote in message
news:IUaVd.48799$W16.14242@trndny07...
First of all, I'd like to ask if Goodman is a top tier brand (as good as
Carrier, et al).

My understanding is that the total cost for the entire system would be
somewhere between $4500 and $6000 for the complete system depending on
their determination of the sizes for the new furnace and new AC units.

First, Goodman is bottom of the barrel.
Second, $4500-$6000 to install a furnace and AC seems like no big deal to
me! We often install furnace & AC for less than $4000! Price does have many
variables though, quality and efficiency of the equipment, labor rates in
your area for example.
If you are serious, get some quotes from other companies. this seems like
they are trying to "sell" you a new system, at regular price or more!!
Greg