For context of the setting, numerous fairly large cities serve as the seats of regional feudal governments in a stable, prosperous kingdom. There are a lot of commerce in the cities, and merchants from near and far visit them for business. Diverse goods, both mundane and magical, can be found at shops throughout the kingdom.
Institutions like book publishers, or wealthy persons ordering construction to be done may sign a contract to someone for future work, but the concept of many end customers paying a comparatively small sum for a future deliverable is yet unfamiliar in this world.
A townsperson might be comfortable with paying ahead for a delivery of wool, which will (unless disaster befalls the shepherd) predictably be shorn and delivered. However, suppose a novel design for a padlock is invented (and protected by royal patent). It requires special tools and a workshop to be built in the city, before the locks can be produced and finally received by the end buyers. How could a townsperson be convinced to pay for the lock ahead of time, on the understanding that the facilities are yet to be built?
How is the concept of crowdfunding developed, and how does it gain acceptance and legitimacy?