These cost issues, frankly, have nothing to do with the technology chosen. They have to do with the people designing and building the lines. The TTC chooses to design and manage these projects completely in house, even though they clearly can't possibly have an engineering or project management staff as experienced at building these mega-projects as a major engineering or project management firm. They also don't operate under any kind of cost constraint. For example, I was reading the EA on the Vaughan subway extension. They examined the possibility of running a segment of the route above ground, instead of tunnelling under empty, government-owned fields. They dismissed the option out of hand, because of slightly less convenient geometry on a pocket track turnout, without even looking at how much money it would save! There was absolutely no mention of the financial impact that could, potentially, be in the hundreds of millions for several kilometres of tunnel and an underground station at the 407 (alone costing close to $100 million).
The reason the Vancouver route could be delivered at a reasonable cost is simply because the company building it had an incentive to save money. Now, I don't believe that the public sector can never economize. The TTC used to be masterful at building economical subway lines, like the Yonge and B-D routes which were efficiently cut-and-covered or even run above-ground wherever possible without excessive impact on the neighbourhood or quality of service. Both those lines operate very well, I think everyone would agree. This persisted well into the 80s, where they produced designs like the DRL where every line of that report talks about cost and benefit, and always looks for the cheapest way to do something without unduly sacrificing the quality of service. For some inexplicable reason, they've completely abandoned that practice. When you read a TTC report, there's almost never any mention of more economical solutions, and if they're brought up, they're quickly shot down moments later with rather feeble excuses. That, more than anything, is why it now costs almost twice as much to build a subway in Toronto as it does in Montreal, let alone Vancouver.
The most important thing people understand here is that cost saving is not about technology, it's not about architecture, it's not about comfort, it's not about any of these things that people usually bring up when they try to cut costs. Virtually the entire cost of the line is determined by its alignment. Deep, tunnelled lines are expensive, and require expensive deep stations. Shallow cut-and-cover or even surface lines are vastly less expensive, and can have far simpler stations. That's where people should be looking if they want to save money.
*And by simpler stations, I don't mean ugly stations! Montreal built its latest subway with gorgeous stations, and for a fraction of the cost per mile of Toronto subways, despite a major river crossing. A shallower station, without an underground mezzanine, or a surface station can be more beautiful than any station the TTC has built in years. Hell, get real architects to design them like we used to, instead of once again letting the TTC do it in-house.
