Your quote could be high, and it could be in the right ballpark. It depends on exactly the amount of labor you are talking about. Stone is always higher to lay than ceramic because it's trickier to work with.

Does that include all of the prep? A floor that will have stone tiles on it will need to be twice as stiff as one that has wood so additional underlayment may be needed or even beefing up the home's joists with some blocking.

Is this a straight or diagonal pattern? Diagonal means a lot more cutting and more time.

Does this include sealing? Marble is porous and will abosrob stains unless kept sealed. Bear in mind that sealing will not prevent etching when it comes into contact with any acidic substance. This means that your installer has to be careful in cleaning grout off of the tiles as any regular acidic grout cleaner will etch it. It's usually better to seal the stone after it's been installed but before the grouting occurs. This is a PIA for the installer and adds time to the process. You pay for the extra time always on any project.

Get more quotes, and make sure that the same exact labor and products are being compared.

$10 for labor is about right for an average installer. A very good installer will cost more.

Yes, it's ballpark. But do your homework about whether or not your floor is stiff enough for stone tiles.

And do not forget an average charge includes all the perimeter stones that are likely to require individual cutting.

Thanks, everyone.

How thick does the subflooring need to be for stone tiles?

Brickeye, are you referring to paying more to do the cutting of the perimeter stone or ordering extra perimeter stone for the edges? i'm nervous about the perimeter now.

"are you referring to paying more to do the cutting of the perimeter stone or ordering extra perimeter stone for the edges? "

Depending on room dimensions ad stone dimensions every perimeter stone may require cutting.

If you do not now how to estimate coverage be careful.

Rooms are rarely as perfectly square as cut stones or tile.
Ad to that the size increment of the stone.

A god job should also have equal margins (the cut stones on oppsote side of the room).

If the room is 5 feet 10 inches and you are using 12 inch tiles, you do not want an 8 inch 'edge' along one wall, but a 5 inch edge on the opposite walls.

It gets tougher when you have a narrow edge of 1-2 inches. the you may have to put up with uneven edges (zero on one side and 2 inches on the other, vs. 1 inch all around).

It is common to put a narrow edge on the entrance wall of the space, and have a full size on the far wall.

You are not looking at the wall you just entered through, but are looking at the far wall when you enter the room.