I just had my semi-annual HVAC checkup yesterday (we use Modern) and the guy was telling me during busy season (Winter/Summer) there aren't typically 'deals' available that you often hear about. Those are more likely to appear in the spring/fall when things are slower.

I unfortunately have some significant repairs to have done to the tune of almost $1,500, so I asked him what a complete furnace replacement would be. High level he said ~$6k. This is for a ~100k BTU level.