The only cost the sources quantify is the first edition's operating budget of 750,275.03 euros, about 2.5 percent of the 30 million euro pot: 350,805.31 euros for coordination and facilitation, 318,937.06 for communication and 80,533.66 for logistics, accessibility and events, against 470,596 euros budgeted for coordination and 81,117 for logistics; the district-by-district coordination spend ran from 17,947 euros in Les Corts to 29,451 in L'Eixample, and voting support cost 39,735 euros. Nothing is given for the 2024-2027 edition. Staff time is never counted, but the evaluators describe internal effort, overload and bottlenecks in assessing 1,982 proposals, running concreció meetings and designing and managing works across districts, areas and executing bodies, and recommend redistributing functions and support to avoid them; project sheets record six redefinition meetings for a single street project and extraordinary meetings to pin down vague proposals. Promoter time is likewise uncounted: debates, concreció sessions, design reviews and follow-up commissions across years, plus the wear of waiting; the sheets record promoters who moved away, gave up, or turned to the Síndic de Greuges after months without information. The opportunity cost row is a reading of the evaluation's remark that the 30 million euros of projects made up part of the mandate's investment plan (PIM) and that citizen proposals sometimes collided with municipal planning; the sources do not say what the money would otherwise have funded. Political capital is spent when districts drop or shrink voted projects, and the evaluators say the process needs consensus across governments to survive. The mental-model row is the evaluators' own account of what changed in the executing bodies: the client is no longer only the area that commissions the work but the neighbour who proposed it, who must be sat with, listened to and adapted to.