Hi,
I would add ; that buying the support equipment for 'E' flying is similar to buying radio in that it is all too easy to buy that what 'will do for now'.
Some of my club-mates have lots of chargers, power supplies and or power sources that are now redundant.
I think it is better to take time to evaluate and to buy what seems to be a bit extra ,capacity wise.
You don't have to use it at max but you then have it if it is req'd. Also you are then not running the gear too hard.
Brian