Ok, I know this is a very open ended topic and there's a lot of variables here. I know you can't tell me how to bid my job just making sure I'm not way off base.
This project is about an 8,000 square foot commercial building, wood construction other than block and footing. It is only a one story building but the lot slopes and the rear portion is built on stilts with the floor level about 18' off the ground at the lowest point.

The rear portion of the building is constructed out of large timbers, i think mainly Fir rough cut. I am trying to determine if there is a value in this lumber that would warrant a selective hand demo for the resale of the wood, or if it would be more cost effective to trash along with the rest of the standard construction materials. Due to the height it will be a project to dismantle as opposed to knocking it over, but the material would be destroyed

The material that could potentially be saved: again mainly Fir

10" x10" x 18' support posts-about 50
4"x12"x20' roof rafters-about 100-125
about 3,500-4,000 square feet of tongue and groove pine from the exposed roof.

I am very good about sorting scrap metals and clean fill but looking for some opinions on the cost/benefit of this lumber

The market around here is competitive like everywhere else so I am not trying to ask around too much locally before the job is secured. It is in central Pa and I know there is a market for used Post and beam building but this is a little different.

Also on the pricing subject, I do not typically use a square foot cost for my final number. I do my best to estimate machine and trucking cost. Waste tonnage and tipping fees. I then review all numbers once complete. With the jobs that I have won I have done well, but depending on what is in the other guys head when he does his numbers we could be way each others price when we submit. I am not a low baller and do not want a job for the wrong price. I would however like to be competitive and get my name into this larger market.

I just looked at the job and my quick numbers are getting me in the 75-125K range..but again quick numbers
How do you guys come to your number these days? My method or a square foot average?

Some things to consider:
175'x45' foot print with some decks and storage bump outs
Its a very open building with minimal interior walls
Landfill is 10 miles away with tipping fees about $70 ton
About 500 feet of block and footer to removed with another 500 feet of 1'x4' concrete wall and footer
clean fill(as of now) will be trucked about 5 miles away

Any insight is appreciated!
Thanks guys