As a systems engineer/project manager who has implemented over 1000 systems, of varying manufacturers, it is not all about the manpower, system engineer, or vendor. Here are some other items involved:
1) Vendor and customer Project manager performance/ communication.
2) Customer response time to vendor project management meeting requests.
3) Prompt response to information requests from vendor project manager by customer project manager.
4) Prompt response to items requested by and contractualy provided by customer.
5) Telco provision of requested telco services.
6) Responsiveness of customer to configuration, and programming detail requests prior to programming system.
7) Extent of customer changes requested during project.
8) Extent of programming changes requested by customer after Initial programming begins. ( some seemingly simple requests require extensive or complete defaulting of the programming and starting from scratch)
9) Providing proper lead time prior to install for proper manning/ scheduling of project.
10) Developing of a good relationship with Vendor, including past relationship with vendors accounts recievables department. (Yes, this matters!)
11) Proper sales engineering, timely signing of contracts, payment schedules during project.
12) Performance of other contractors providing critical services. For instance, cabling infrastructure completion. electrical contractors, local telco, LD carriers, environmental considerations for equipment installations (HVAC).
There are a few dozen more items depending on whether one company is handling some or all of the items in number 12 above. As well as requesting work during national holidays, after hours or weekend requests for completion of work load. This generaly requires additional charges. Finaly, condition of existing cabling infrastructure, and overlapping of project with other ongoing projects which inhibit access to facilities, or work space.
I submit deadlines with all requests to the customer with notification of assured impact on completion dates for the project. Including holding back scheduling confirmation until completion of certain specified items.
The project is dependant on all parties involved to complete satisfactorily, and promptly.
You do not always get what you pay for, but you never get what you do not pay for.