Where is furnace located? Where is ductwork located? You need a return for upstairs. I see nothing wrong with the 113 model. It is low end Legacy series in the Bryant line. Does carry a 10 yr warranty if properly registered. You will need best matching ALA aluminum Bryant coil. Not necessarily noisy but a rating of 76 db. As far as footprint, your dealer should give you the dimensions. IMO

The questions you should ask is how did the contractor determine the sizes of the furnace and AC. I see you have an very big furnace (140K BTU input), and I think a 3.5 ton AC. These appear to be oversized, but a load calculation is the only way to tell by how much. I would also ask the contractor to inspect the duct work for possible issues and discuss any heating or cooling problems you may have. The quote should list the model number of all pieces of equipment. It would be good to get the AHRI number. This insures the system is an approved match. I would also like to see which thermostat and filter are included, and the warranty. You will need to get new quotes. Prices and models have changed.

I do not understand why he would oversize the BTUH of the equipment way above what the ductwork sizing will support at reasonable static pressures & FPM velocities. A tech may have to figure out another way to run ducts to those rooms. The linked page will provide some guidelines toward proper duct sizing. It appears you would not need much air conditioning tonnage. I am a retired HVAC/R Contractor since 1993 & do not operate an HVAC/R business or work as a tech anymore. udarrell _ 2007 Here is a link that might be useful: udarrell.com

I was able to get info on the existing furnace from the data plate. It's a Carrier Model 58ss140-BC, Series 110, 167,000 BTU. The data plate said the blower is "157", whatever that means. The motor spec was 1/2 hp. Mfg date 1982. That's all I found on the furnace. I found next to nothing on the a/c. The data plates outside are gone. I could see where it was but there was just rivets. A single, long rectangular unit outside. Like I said, vintage 1974, from the builder. According to my mother, the quoting contractors guessed that the system was 4 or 5 tons. I don't know anything about who said what. Turns out the Lennox/Costco guy was the only one to quote an upgraded unit. He also quoted: Option #3B. $9,185. Platinum Package. A/C XC17-048 and 2 stage gas furnace SL280UH135 with variable speed and I-Comfort Communicating Controller. I'm having a hard time getting her to look at the Am Std quote because they didn't quote her an upgraded unit option and their basic units were only about $1,000 cheaper than the upgraded Lennox units. ($9,145 vs $7,945). About the house, I tried to describe it above. Built 1974. 3200 sq ft. and two stories. Attached garage. Full sun exposure--the property is not shaded. Brick exterior with not a whole heck of a lot of insulation. (I remember my parents being mad that the builder gipped them on the insulation.) High quality house though, expensive neighborhood. Stick framed over a full basement. Attic with pitched shingle roof. Colonial. Original single pane wood windows with storms windows, maybe a tad drafty. After being widowed with 4 kids in 1978, she never had the money to remodel anything and everything is pretty much 1974. Anything else you want to know about the house, please ask. This is all I could think of.