Simple CAD Drawings/Mechanical engineering

We need a couple of simple metal components manufacturing for us, but we have no CAD capability in house so we find it hard to provide a specification that is more precise than a rough hand drawn sketch. Your job would be to take our sketches and descriptions and produce a CAD drawing that will give us an exact specification. We can then get quotes based on the drawings knowing there is no uncertainty over what would be delivered. There could be several small jobs like this. The first one which you should quote for is the design for a stainless steel cylinder shaped water heater tank and an electric heating element that is joined to the tank with a flange. The tank has in inlet pipe and an outlet pipe. The drawing need only concern itself with the shape of the tank and the element - you do not need to worry about how it might be made (for example where the welds in the tank might be). Successful applicants should have CAD expertise (please specify software) and ideally mechanical/electrical engineering knowledge. There are likely to be several small projects similar to the first, these will be re-advertised on the basis that the initial winner will be awarded the follow ups too assuming the quality of the first project is OK.