I have looking at replacing a furnace and AC UNIT with a Luxaire 98% AFUE and a Luxair 14.5 SEER 3 Ton Unit what would be a fir cost estimate

I have looking at replacing a furnace and AC UNIT with a Luxaire 98% AFUE and a Luxair 14.5 SEER 3 Ton Unit what would be a fir cost estimate

Actually there is no such thing as a fair cost estimate since each job is different. Different locations ,citys,states charge different labor rates and markup on equipment.
The best thing you can do is get at least 2 different estimates. See item below.