I was wondering which warehouse/fitter has the best deals/value in the Chicago region. 

I asked the question of BP but received no response.AIA, PE, LEED AP etc.Maybe Mater Plumber, Gas Fitter, etc under licenses as well.But good question.

Welders, boilermakers, fitters. 

There might be some quicker/cheaper options, such as Bath Fitter (no affiliation, and not event a huge fan...but any port in a storm, right?).

Has anyone ever used the line they sell at Home Depot called Bath Fitters?

I pick them up for $9500 and rent them to welders, fitters, boilermakers, electricians and inspectors from Texas and Louisiana doing contract work at a refinery. 

I'd recommend you discuss your particular structural layout with a "Certified Pipe Fitter" for more pinpoint advice.Happy Holidays,Eric Love, Original Paper Landlord, LLC, andBoardwalk Luxury Apartments, LLC 

I've had electricians, welders, fitters, boilermakers, prostitutes and strippers in there.

Then I got two guest (doctor and pipe fitter) that seemed to complain about each other constantly even though both of them worked about 16 hours a day.  

I would look at joining the trades(electrician, pipe fitter) especially if you could get on the traveling circuit working at nuclear plants.