Customer chassis a way to control cost?

[Taxi645]

I think the customer philosophy is a very effective way to control cost. For instance on engines saying to engine manufacturers after 2020 you are obliged to offer the engine you race with for a set price (that small teams can afford) and the business model and the competitive logic of insanely expensive engine programs erode quite quickly.

How could a similar approach on the chassis side have a comparable effect. What if say a Force India or Torro Rosso level chassis were available to third tier teams for a set and reasonable price? The FIA/liberty making sure that it's worth their while for the chassis supplier/

Would that be a good approach to enlarge the field and help to keep cost down for third tier teams (think Manor) while providing an additional revenue source for a mid tier team or would that undermine the business case for too many teams to developing your own chassis and thereby reducing engineering capacity and diversity of the field too much?