Virtuemart Child product Modifications

We have a Virtuemart website where we have custom made product options with child products. We need a person who can make a combination of the products. The developer has created for us a Virtuemart system now we need a person who can add possible options for two products with the thumb (model) and main image. We need a developer who know the Virtuemart and who will understand what should be created. The combinations for two models and products. This means if selected model one for each step what main image should be showed. As well if selected model 2 for each step what should be showed as well.