Here is a link to a prior response that might help you - the response itself might not be much use, but there are links to several other more pertinent ones right below it -
https://answers.angieslist.com/what-r...
You are basically talking a loose largish mosaic tile, which is a LOT more effort to get right than normal sized tiles, so I would guess you would be in the $10/SF range for a full kitchen backsplash - more if just a short section, with probably about $200-250 minimum charge. That cost would include everything (including about $1/SF of misc materials) but the tile itself which you apparently are furnishing.
