The building is approximately 10,000 sf and is currently being used as a rug and fabric store.Thank you,Luan.

or just decide you were pissed and your delicate sensibilities are more important than critical thinking?

Structural Insulated Panel System (SIP) framed houses can sometimes have large cost savings or Machine Framed walls and rooves can be constructed in-factory and then assembled on-site (and they aren't considered "pre-fabricated").What I would do is:1) Break out the phases of the construction   Architectural Plans/Construction Documents/Building Permit  Grading and Drainage  Foundation  Framing  Windows and Doors  Mechanical (HVAC)  Electrical   Plumbing  Drywall/Finishes  Fixtures  Paint2) Identify what you can do yourself (best way to save money), remove it from the scope of work3) Research or solicit bids from several contractors asking each for a price for all of the above (they may need a set of plans, so that'd be the best place to start)4) Research unique or creative methods of getting each phase of the project done    i.e. - Maybe you can get pre-made architectural plans that are easy to modify?         

They are some sort of yarn or fabric strings that I've never seen before.

Since this is a delicate situation I don't want her to move out and then he says that he never agreed to such a thing.Thanks so much!

You should probably furnish the house with furniture that can hold up well to rough handling (no dainty fabric furniture).  

I work in the home improvement industry as a Sales Manager for a stone work company specializing in the fabrication and installation of granite, marble, and quartz counter tops.

I think there's a delicate balance of coming prepared, asking what can you do for me, and getting some comparisons and wasting everyone's time.

Its honestly a delicate balancing act.  

That being said, you CAN save money IF you do fabrication systematically and do multiples.