xpensive - costs could be capped by ensuring customer teams can purchase the systems say a fixed price. Current tariff is 1m for KERS, 5m for an engine.
A future integrated system is likely to include/replace the gearbox, so let's say 7m for the full package?
We'll end up with Merc and Fer spending a fortune with a small contribution from 2 customers. Cosworth will raise funds by selling to 4 or 5 teams.