As an update as of now it cost 12-15$ for one pair of dress pants. It goes me 12$ for 2 inches off.
When it comes to alterations it would probably be best to talk to the guy that does the alterations. He works strange hours and it is not every day of the week. So the best thing is to call and find out.
I remembered seeing $14 for the pair of slack but I stopped going at this particular location because they don't take care of your clothes very well over there.
They have a tailor that comes in a couple of days a week you have to call to find out the exact prices I'm not sure
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