Film can be cheap: you can buy 90 meters of Polypan for 30 euros, you get empty film cassettes for free in any film lab. You develop in rodinal 1+100: cost are less than 2 euro cents / frame.
I don't want to say it is a best film, but cheap it is: more than 2000 pictures for about 30-40 euros.
That's cheap, but Ratty is shooting MF, not 35mm. Yes, his shooting costs would go down if he shot 35mm, but he's nuts for a large negative, and so am I. I totally understand his desire for MF.