Correct, exterior surface area plus any returns.

I'm curious - what is he suggesting that is cheaper?
Around here, everything else costs more (Siding, Cladding, Masonry....)

Surface area. Perhaps consider cheaper alternatives, like a combination of stucco and siding?

Naween, is stucco extremely cheap where you live? Here, it's also about $8-10 per sq. ft. if you want a light color.

Compare that to a premium siding at $14 for an 8 sq. ft. piece. Making it just $1.75/sq. ft. in material, and I'm curious if the labor costs would be another $6.25 per piece...considering it takes about 1 minute to put a piece up, with minimal skill unlike stucco.

Stucco requires a scratch coat, sometimes a mesh layer, and there's premium costs for some colors (darker for example). VanillaCottage, you could focus on having the front face of your home stucco if that's the look you really love, and perhaps opt for siding on the backside to save some costs? Or again, perhaps do a mix of the two? Many homes have this and it looks quite nice without the premium costs.

I checked our recent quote and it was $6/square foot for (light colored) stucco.
Its used for >75% of new homes here, though, which may drive down the price.

All the fiddly bits of corners and such may also increase the price of siding, whereas in stucco you spray it and walk away?

Naween wrote: "whereas in stucco you spray it and walk away?"

My stucco was put on by hand in multiple layers.....over several days time......is it really "stucco" if its sprayed on??

It's more common than perhaps you think?

Eg, this website clearly states their stucco can be sprayed. http://euclidchemical.com/fileshare/ProductFiles/techdata/Tamms%20Stucco%20Finish.pdf

Acrylic stucco, especially, can be sprayed. It tends to allow darker colors and (i could be mistaken but) i think it may also be more durable.
(Eg i found several via google to show you, http://www.supertherm.net/as_application.htm, http://www.durock.ca/finish.html)

There are also cemetitious concrete sprayers available as well, but around here the old stuff is considered 'old technology', and is rarely used except to repair older homes.

Of course, if you want one of the older 'hand troweled' finishes, you'll have to pay substantial man-hours for the work.

Naw....what part of the country are you in?

Here in California, I've only seen it applied by hand.

$10.00 a sf here and they don't deduct for windows or doors.

Architect hasn't suggested anything cheaper yet. And quite honestly, I don't like the look of those homes that have stucco or brick or stone on the front and then siding on the sides and back. Just looks tacky to me. I think I would opt to make a larger part of the budget go to the exterior cladding if I have to. It might be okay to mix them if they were on separate sections of the house, like a house that was added onto over time. We have lots of those here, like the pic below. We haven't even designed the house yet, but that's something to keep in mind while we do.

I think location probably affects cost of stucco too. I suspect Naween is in one of those places where it's very common, like the Southwest or California. We are in the Northeast, where siding is the most common application. Stucco houses are rare, and those we have were usually built in the early 1900's. And of course, that's the look we are after.