In general "here" mean your location "I'm here". "There" means something's location "you are there".
#1.
(A) Yes, this works. (D) also works ,and its slightly better. "Here take it" says that the customer must go take her own change, but in (D) she is being given it, which is helpful/nice. "Here" is the change, for the man, and there is the womens wallet, again to the man.
(C) again works but it would need a comma "There, you have it". (B) is awkward, its something you would say to yourself, not the customer, as to him "here" is the change, to say "here it goes" is basically saying "This money, is leaving me" which sounds greedy/selfish.
#2 (A) nearly correct, but the sentence is not in the right tense, its in the present, when you are talking about the past. "how DID it gET there" . (B) and (C) are awkward. (B) could be written as "why did it go, on you" but this is after she said, she thinks she got it off the chair, so there's no need to ask this. if you're wondering "on" can refer to both you're location "on me" "on here" or someone's location "on her" "on there".
. (C) is hard to understand, but seems like its asking what action did you do to get this run off the chair, so "What brought it up, off the chair" but I do not think you are asking that. The location (you're location/ there's) does not and is not in the sentence as you can guess from the context/(previous sentences).
Sorry if my answer is too long or hard to understand, any problems just ask. Good luck!