Set of ICONS designed

Industry: Technology
Design details: We have a requirement to produce a set of icons to represent requests within a retail environment. The Icons should all follow a theme/style.

Simple to understand using a maximum of 4 colours + background
Additional icons will be required in the future, so a simple design scheme should be adopted.

Within the described requirements, figure identities such as Customers, Colleagues, and Managers to be represented within the icons should be clearly distinguishable within the images, and have continuity across the different icons.

Icons should ideally be scaleable vector (AI) files.

Typical size of the printed icon will be 15mm to 20mm square.
Ideas for the visual style: Simple and clear, a style which can be re-used for additional application types. For example, we also have a telephony application requiring the same icon theme.
Preferred colors: Single or dual colour icons work well, perhaps with a feature highlight colour
Where the design will be used: Print, Screen, POS and Telephony equipment
Extra notes: Please see the attachment for an outline of the initial required icons. At this stage we are looking for a designer to devise a reusable theme, and to demonstrate this though the production of a small set of icons.