A production system is a set of choices: seasonal room or environment controlled, own compost or bought compost, own spawn or bought spawn, ready to fruit bags or substrate from scratch.
Everything you make adds capital, skill and risk, and removes a dependency. Everything you buy saves capital and hands a link of your quality chain to somebody else. NHB's DPR template treats spawn, casing soil, compost, ready to fruit bags, cropping and processing as six separate components for exactly this reason.

