animated musical video

Hi, We are working on launching a series of animation for kids. We intend to hire professional group who can provide original musical animated videos for pre-school children. We need videos similar to the below video on youtube. [login to view URL] The project will be long term hence we need you to quote price for every 10 videos considering 200 videos currently however the work will be given on the bundle of 10 videos per month. The project will be extended every month based on the quality of previous 10 videos. The video should be 2D/3D animation with nice music and voice over. The video length should be more than 3 minutes and should not exceed 7 minutes. While bidding please provide some samples or portfolio.