standard in KL if RM 13 to 18 no one dare complaint.
but in smaller housing area, klang valley, chap fan range from RM 8 to 13.
is normal here.

but is smaller town or states, not sure what is the rate.
maybe RM 13 is over price.

but then no need aggression. just politely return it can already.

if i feel my chap fan too expensive, i will ask the seller how you kira.
simple as that. if they can explain it, then ok. if not usually they say sorry and charge cheaper.