Are you allowing for kerbing and drainage? Do you want the trees taken out, the roots totally removed, concrete taken up, etc, and what else do you need to do before you think of laying anything? Lots of people come on here looking for ballpark figures in regard to getting prices for "small jobs", but they're seldom small jobs. As a matter of interest, what do you think you might be paying, give or take a thousand and don't go telling us you haven't a clue? I'll give you an idea then of what I think.