Living in NJ

Existing Central Air system (heating separate) is installed in 1988. It's SEER 12.5 RHEEM (3.5 tons). All the duct-work is in place and good condition.

2200 living space with lots of windows. I was recommended a 3.5 ton replacement.

Split level home. (I would love to have dual zones not sure if it's possible as there are no doors between upstairs and downstairs)

I'm looking to replace the air handler (condensation coil), air cleaner(filter) and the outdoor unit(A/C).

I got a quote from a Carrier rep:

Carrier, 24APA542A 15S,

FE4ANB006T for over 10K dollars.

I would like to get a quote from Costco guys and one from Trane, but it feels that they too will be steep. I'm about to go back to finding someone to service my unit instead.

I have also heard here that in NJ I can do Energy Eval of my house and potentially get some rebates along with repairs. Can anybody point me in the right direction as to how that works? I would like to also get my attic cleaned up too (there are some mouse droppings and I discovered that my insulation is flat at this point.) Are there any such all in one companies out there that would do a good job for a reasonable price?