The dollar can be used once a day. It has to be a dollar’s worth of a product, service or use of a product. For example, A dollar’s worth of a $100 TV would be the life of the TV divided by 100. You would get to enjoy the TV for that amount of time. The product or service is instant and doesn’t require any preparation. It just appears and disappears. Or you could have a TV permanently that is worth one dollar.
So what happens if the thing I buy is information? Technically would have infinite lifespan— but if I only remembered it for a certain amount of time (if tied to a service or something, maybe could copy it before the time ran out, eg in the case of a movie or Death Star plans etc)