They should say we negotiate the heck out of our suppliers then market up their products 14%.

I'd also suggest you have alternate suppliers and SKU's for your items.  

They are a contractor or supplier.

Pipe inspectors, directional drilling tools, mud companies, trucking companies who move rigs, cable suppliers, motor parts, machine shops, tire sales, the list goes on and on. 

To maneuver it in the Garage,  you might want to go get some large cardboard pieces from a Garage Door supplier or installer.  

The window/glass supplier knows exactly what this means. 

It doesn't mean they'll pay it, but remember a few things. 1) you can base your price on supply and demand, and lucky for you they've got but one supplier -- they cannot simply go into the market place and just buy a building.

We have terms on our suppliers, and we do payroll every Wednesday, so a simple fact is, if we get paid before we pay someone, then we can pass savings to you, otherwise if we let you use our money (common in new builds), then our bill/pricing starts to run upwards.

Well after contacting my supplier, we couldn't find out to fit into the wall sleeve.

Like@Brandon Battle posted, a good contractor should have a good suppliers list, where they generally pay for wholesale price.