Package design for teeth whitening strips

We will require a mock up before starting to work with you, if you refuse to make a mock up for us before deciding to work together, please do not make an offer. I am looking for a long term collaboration with our company, as we have dozens of products that need package design, that's why we are not looking for someone just in need for a one time job. We have already the concept in mind, the logo, we just need someone that has the skills, the will, to work with us on a long term.