Many of the spells in the Basic Rules indicate that they require material components. For the components that don't have a specific cost (I tend to call these mundane components), the Basic Rules state that I can get the components from a Component Pouch.
Component Pouch. A component pouch is a small, watertight leather belt pouch that has compartments to hold all the material components and other special items you need to cast your spells, except for those components that have a specific cost (as indicated in a spell’s description).
D&D Basic Rules v0.1 | Page 48
How many times can I cast spells using a Component Pouch as the source of my material components, before the pouch is empty? (Or, having purchased a Component Pouch, do I now need to go out and source all of the material components I am going to need?)
RAW answers are preferable, but in the absence of those, working (tested) house-rules are acceptable. If your answer is a house-rule, please make that clear in your answer.