I agree with Les; what I will do for a known GC is different from what I will do for a stranger.
Likewise, one cannot do an acceptable job without a great deal of communication between you and the final customer. Let me explain, usung a job I've been working on.
Last December I started a "dream job" for a customer with whom I have a long relationship. I was given an essentially blank print of their new headquarters, and told to make it work.
The building is a steel building. The office area is two floors, about 30 x 70ft. The Shop area is about 70 x 150.
Knowing the customers' business, and the area, I went "against the flow" and insisted upon 480v service- over the objections of the PoCo.
Seeing that the office area was framed with wood I-Joists, I realised that there would be no going back latter to add or change things- so I took care to light the place well (striving for even light), gave each room two levels of lighting, and installed plenty of receptacles. I ran an outrageous number of phone/data lines. In some cases, I used my past experience as a "working stiff" to look at how each room was likely to be used, and added some unexpected things- like the phone in the lunchroom and the hand/hair dryer in the locker room.
Of course, now is six months later, and as the project is coming to a close, I am only now seeing that someone has decided to put an L-shaped counter in the lunchroom; the sketch I was shown either had no counter, or a straight one. I made my best guess based upon the plumbing.
I am being pressed for when I will have the power run for the various items of equipment- even though I have neither seen the equipment nameplates, nor have they decided on the locations. What I have done is stub out a pipe from the panel for future circuits.
I had "stalled" in a similar manner until the A/C was on site- a good thing, as the A/C folks 'did what they always did' and used 240 single phase units. That's right, they never even asked what power was available, and missed an opportunity to use the 480/ 3-phase available.
The point of this tale is that, even under the best of conditions, change happens. Your first 'bid' is at best a wild guess. With an unknown contractor, unknown customer, and no idea what they want, you are only asking for trouble.
I would prepare a rough plan of what you think is wanted- then sit down with these folks and hash out what is really wanted.
On the job I mentioned, some thought the provision of showers in the locker room was extravagant- not fully appreciating that the customer cleans serers all day- and really needs a shower before going home!
