Depends on the size (tonnage) of the unit, the SEER rating and of course the labor. I don’t consider that ridiculously high and I’ve bought 4 of them in the last 4 years.
Unless you have sheet metal ducts I’d almost bet you need ductwork too. A lot of the “older” flex duct is complete crap and it’s almost NEVER installed correctly-too many and too sharp-bends.
Try another dealer and brand. For that kind of money its’ worth getting a couple of bids.
Try goodmanmfg.com. Find a local dealer to do the job. My experiance is that they are among the less costly because the equipment is less costly. They have the BEST warranty of all manufacturers. I worked there for 18 years and am still dealing with them. I am a certificied contractor in Florida ( the hardest stste in the union to get a license), I know of what I speek.
The cheap stuff that we used to call builders grade had a 10 SEER rating. Now, to meet current codes, I can’t install anything less than a 13 SEER rating. In a couple of years, you will also have to install a Puron system because the R-22 coolant systems will no longer be legal. Today, more expensive systems are required to meet these code changes.
Contact your electric utility company. Ask if they have a financing program for replacing your current system. I did this for a couple of my properties. They gave me 100% 5-year financing at a favorable rate and a list of approved contractors who can do the work.
I called a couple of the contractors on the list, told them that I was replacing my heat pump system under the utility company’s financing program and asked for quotes for a replacement system that met the program requirements. Once I got a bid, I submitted it to the utility company for approval. They approved the bid, inspected the work when done, then sent me a check to pay for the system in full.