I've seen many tips on where to get Flower Gems, but very few about how to spend them. I did learn that expanding the equipment storage is inefficient, and that it's best to use the Flower Gem gacha only in 10+1 draws.

My questions are:

1. How many times can I expand the character capacity? Or rather, how many gems must I spend to expand it to the max?

2. Is there any difference on how many Flower Gems I spend per month? For example, any "spend 50 and get better login bonuses" deal?