Perhaps if we removed all the waste costs, like consultants, etc: then perhaps we could get many stations reopened, and more people would have access to the rail system, which will increase its use and profitability.
I suspect that there are actually no easy ways to cut down on waste costs. Metro (and probably the entire rail industry for that matter) are aware that stations tend to be expensive, but local halts need to be built as cheaply as possible (whilst complying with the requirements of modern station specifications) otherwise they just won't get built. If you look at the plans for Apperley Bridge you'll see it's quite a basic design - it reuses an existing overbridge for access, each platform has a glorified bus shelter etc.
Yet somehow it still costs several million. Clearly engineering consultants need to be employed for the design (Metro and Network Rail don't have the different skills needed). As for other forms of 'consultant', do you have evidence that they have been employed, and if so in what capacity? It would be very odd for cash-strapped Metro to spend unnecessary money. I suspect we should look at the following areas for cost increases compared to stations built in the 80s and 90s:
- Higher specs for stations - DDA, information systems, etc etc.
- General inflation in materials and skilled labour (usually higher than CPI).
- More planning - environmental statements and so on.
- Need to produces acres of reports to central government to get funding.
- Far more onerous safety requirements for construction in general and working on the railway in particular.
- Complexity of the industry - too many players ("stakeholders") means it takes a lot of effort just to keep the thing going in a steady state, let alone change things.
- Need to compensate train operators even for planned possessions.
- Possibly more rolling stock needed.
None of these are in Metro's or even Network Rail's power to alter. Of course modular platform systems have been developed to reduce the amount of time the railway needs to be shut for during construction, but it's not enough to offset the other issues. It's an intensely frustrating situation and looking at the rate of station openings over the past 30 years it does appear to be the structure of the railway brought in at the time of privatisation that has caused this.