1. I buy all my teas in either 'ban jin' or 'yi jin' quanities (250g
or 500g) mainly because that is the most common quantity to buy tea
here in China (most shops only sell like this). Some shops are trying
to sell teas in increments of 50g and up the prices claiming it's a
'high quality tea' but most know the wiser and don't buy in their
shops.

2. I drink in shop before I buy. I do have 3 small sample packs of
some TGY that a boss friend gave me, though.

3. I have much random green tea that is nameless and can only be
classified as green tea. Such teas I acquired as gifts from various
people. Most of it is cheap, but is suitable for everyday consumption
at lunch and dinner. A good stock tea to have.