They are the same no matter what currency is that and maybe its possibe that price could be higher in the current price if you wanted to buy in a local exchange site(of course using your own local currency)but lower than the current price when your going to sell.
so true . it depends on the price of an exchanger. we find it difficult to get the lowest price. because almost all exchange has a price that is not far adrift. for me is getting exchange of reliable and safe. it is the most important thing.
No it depends also in law of supply and demand. For example every halving of bitcoin there is a certain matter that the bitcoin will rise the value and it is definitely double the previous value so it is a law of supply and certainly the currency of your country will definitely low in the value bitcoin therefore it is a law of demand.