Is it possible they are really busy and quoting high because they don’t want job? That happens in my area sometimes. They have plenty of work so they quote a ridiculously high price... if someone still hires them then they’ll bump someone else since they are being overpaid. But they mostly count on pricing high to take themselves out of the running.
We have had energy consultants from electric company out a couple times and it is worth their expertise. They can tell you about any programs or rebates that may be offered in your area.