Re: how much does it /did it cost?
You could use "How much does it cost?" when you are talking about a general fact. If you know that your friend always gets his hair cut at the same barber's (hairdressers), then you might be able to say "You always get your hair cut at Luigi's! How much does it cost?" That way, you are not talking about the cost of one particular visit, but you are asking about the prices.
Remember - correct capitalisation, punctuation and spacing make posts much easier to read.