Your post tells us nothing about the actual scope of work for the project. Roof pitch, height from the ground, complexity, number of valleys, condition of the decking, actual materials chosen, difficulty of access, and a dozen other things that go into giving someone a bid on the job as a total. You're not buying just the basic roofing material after all!

Does "a square" mean "a square foot"? Even if it were solid gold, those quotes seem wild! Let's just take a normal house measuring 30' x 40', or 1200 sf of roof. At $900 per sf, that would mean the roof replacement would cost about $1,000,000. That cannot be right!

A roofing square is 100 square feet.

A 1200 sf house with a basic single gable 6/12 pitch will need almost 1400 sf of roofing, or 14 squares. A LOT more goes into it though, as that's just the basic shingles. With metal there are all kinds of trim pieces needed, and they are a lot more expensive than the roofing is.

In the OP's scenario, if the home was your basic 1200 sf single gable ranch, the roofing job would be 11.5K, which would be reasonable for a very high COL environment like the Bay Area and using a premium architectural shingle. Location is a HUGE driver on labor costs.

The metal would be around 18.5K, again, right around what you'd expect, to a little low, depending on the type of metal. Metal is usually about 2x the cost of asphalt, due to it being more persnickety of flatness in the deck, and just being more difficult to do correctly. Plus the material cost differences as well.

Here is a link that might be useful: Roofing Calculator

Location location location. Can not be denied as a factor.

Do you seriously think that you can compare base material prices with a turnkey total? Try pricing cake flour and a wedding cake. You're buying the knowledge and skill that it takes to turn that flour and sugar into something edible and beautiful. Same here.

We are in the "cheap seats" of the area where you live and our very basic roof on a very modest sized ranch home was about 22K...multiple bids, all in the same ballpark for a concrete tile.

Thank you all for the follow up. Yes - 100sf is a square. I have to chalk the high bids up to the one post: location location location. There is really no justification for the high bids except for that in my opinion.

Here we call it "the hill tax"--as soon as they figure out where we live, the price goes up.

The tactic here is to get a general quote, say by square footage, BEFORE they know where you live, and keep repeating that sq ft cost when they come out for a real estimate, so they can't get out of it as easily.

I wonder if considerable travel-time is part of the cost in Carmel--which is a legitimate cost--gasoline, travel time. I can't imagine roofers being able to live anywhere near there. And there are other legitimate costs--permits?

Carmel-by-the-Sea is far from the most affluent area in California. It actually lags the state average for households with annual income exceeding $200K.

Not to say the OP's home isn't the exception though.

I regularly run into the "location" problem building high-end homes. All you can do is get more competitive quotes and seek recommendations from friends and neighbours. Also, neat "trick" I practice is driving through new subdivisions and by new infill to see who they are using. Many of the trades I use do not advertise at all.