re: What do licensed contractors charge Sq ft to gut walls to ceiling?

This..

When I do a job, I usually give a person the option of doing their own demo. (mostly b/c I hate demo) If you're nervous about it, just watch a YouTube video or just ask here. We're all more than willing to walk you through it

I'm a commerical contractor and dont mess with the houses but will offer this after seeing a few quotes from (according to the TD) reputable local home builders sending quotes in the 7-9/SF demo of only 4'. I am simply floored and offended.

1. If you have the resources to do the demo do it yourself. Get some Labor from Home depot and go to town. You need of a crew of at least 6 to make the work flow and productive. If Not there will be down time swapping from demo to clean up.
2. If you have flood insurance or just dont want the headache or work, hire a contractor. a 3000SF house, gutted floor to ceiling, removal of damage furniture, including all floors, cabinets, doors, trim, plumbing fixtures, etc Should cost no more than $4-5/SF. A 3000 SF will take a crew of 10 about 2-2.5 days to demo(correctly) and clean everything. In the demo make sure they include the removal of all of the screws from the wood after the Sheetrock is removed.
3. If your contractor is quoting per SF make sure you understand if it is SF of Sheetrock or SF of house. I have seen quotes at $2/SF of Sheetrock. That could add up very fast! Get a lump sum quote.

Some things that need to be considered is the plumbing pipes and fittings need to be properly protected and capped and electrical wiring needs not be damage or nicked.