I also only buy the fly more kits so starting out with a minimum of 3 or 4. when flying a camera drone, I will probably only use 2 or 3 for that session but it helps to have extras if you need them even though I have a power station (charger)...
Here is a fun little example I heard.
The town you live in gets a new big shopping center. You are a Recreational Drone pilot and a person interested in construction.
You take your drone out each day and film the progress. after a year (or 3 if a...