It is a challenge for sure, but in this particular case its all been figured out already pretty much by the people behind it, its a business afterall (This isnt so much a 'boutique' setup, its looking to be a mainline pinball supplier with a reasonably substantial factory etc.. plus these are not being produced solely for the home market, theyll be targeting ops in a big way..), and as such has investors and the like putting up capital so everythings had to be costed in order to produce a business plan with relevant financial projections etc..
No-one would have stumped up money without an idea of how much the things will cost to produce, quite a lot of works gone into this already to be fair.

Im sure Andy (The owner of heighway pinball) will post on here soon enough and answer peoples questions, but i can tell you theres some REAL interesting aspects to this project that will genuinely set it apart from the other pinball producers.

I wondered about that too, partly because I run an IT recycling company and so have access to ridiculous quantities of mid to low-end pc's that we basically destroy for the scrap value of their pcb (Precious metals content is quite high on these) so I know these can be sourced for a few pounds each - I think it was something that was talked about but they went down another road in the end (Tekky reasons i assume - unless you really reinvented the technology that makes a pinball machine 'tick' i cant see how you could avoid some sort of power/driver board etc.. by which point you might just as well create your own proprietary full boardset ).

I cant exactly remember off the top of my head but didnt the new canasta people use a pc system board of some sort?