求英语作文 写一个新买的东西150字以上

Dear Sir or Madam,
I am writing to request for a full refund of the camera-Canon650D I phurchased on Nov 12, 2012 from the XX District Branch Store. (交待写信目的,购买的商品型号,时间,地点)The camera was great when you showed to me in your store, but the one I received was scratched on the lens with a broken shouler strap. What's worst, the camera cannot work as the screen is blur and blue. Besides, the extra battery You shop promised free is not inside the package. (点明退货原因,镜头刮花,肩带破损,屏幕蓝点)
I really like your great service in the store, but the goods is a little lower than my expectation. (先给糖后打一棒子,英语公关类书写中也有委婉语这一要求）You have mentioned a 7-day validity for exchanging or refund unqulified quality, so I would appreciate it if You Store could offer me a refund.（再一次理直气壮点明原因）
I am looking forward to your prompt reply.
Thanks!
Yours Sincerely,
XX