whatever is to hand is fine! as long as the receipt has the name of the work/artist/circle on it the language doesn't matter i can read both of them. i just want to verify that the artist received compensation for their work at some point, even if its a preowned book from shop2000

two characters is fine too. if it's a full set of 15 icons of one character with a second character appearing in say 4 of them, it's +$0.50 for each time they appear. i wouldn't split a set down the middle though with say 7 icons for one character and 8 of another (i think it actually ends up cheaper to buy in sets of 5 then).

if it's 15 icons of 2 characters in each one i'd have to do some math because i don't think i've ever done that haha.