The money change office in Hisaronu have two main methods of getting 'extra money' from you (and we have been caught out by both).
They either change at the wrong rate and dont provide a receipt
If you ask for a receipt they try and 'lose' 10 or 20 Lira. They are good at this and even when they count the money in front of you and the money looks right money still goes missing. You should always ask for a recipt and then recount in front of therm. The problem is that very few people do.