To start with, we need to view – “decompose” – each object in a small number of “primary” or “raw” natural factors that are material; after all, a car is only made of known amounts of iron, rubber, plastic, lead, copper, lithium, etc, that can be estimated. There are only so many types of engine, tyre, battery, etc, and the amount of each factor they consume can actually be estimated.
To make something we also need the “facilitators”; iron doesn’t turn into a car by itself, so we need energy, air, water,… anything I missed? Of course we need also manpower to provide the knowledge of how to transform a mass of raw materials into a car, but I think we can leave that out while we concentrate on natural (rather than human or economic) limits.
I’ll start with my best guess and then hopefuly someone more knowledgeable will read my post and improve my guess. Iteratively, we’ll get the best estimate.