Look at the replies to the same question from John below on January 10th,,,some of the replies actually gave some cost numbers. I would get several more estimates to see if they are in the ball park about the same, however factors like the quality of the vinyl material (i.e. thickness, color goes all the way thru or not, etc.) may make some of the estimate much more different. I installed vinyl on my detached two car garage about 10 years ago and I used lnexpensive vinyl from one of the home centers like Home Depot which I beleive I paid about $40 dollars per square (covered 100 square foot of wall) and I did not cover my soffits and facia boards with anything--left them bare painted wood.
It turned out looking pretty nice and was not too difficult to do....the vinyl can be cut easily with a circular saw and the blade turned backwards to keep from chipping the vinyl as I sawed. Your bid sounds high, so i would get several more estimates from other reputable contractors-being aware of the material quality and difference from your existing bid. Hope this helps and good luck. Post back up with your final outcome.