As for how I prefer to buy, I prefer just individuals as opposed to lots. However, if it's something like Barbie dolls (non artist and non resin dolls), I tend to group those since they don't seem to fetch good prices by them selves.

I would charge shipping, as with the way things are now, shipping seems to change too much based on dimensions of a box.

Offering discounts for multiple purchases is nice, so it helps move things.

Best wishes and sending hugs your way.