Webshop with Shirt Designer (like Spreadshirt)

Good Morning everybody, We are a small company from Germany and want to improve our Website. We doing embroidery, T-Shirt print and heat transfer on Shirts, Jackets, ... That’s why we are searching for a company to build use a new web shop. The Web shop needs to have two Parts. One Part will be a Configurator for Customized Designs and one will be a normal web shop for finished products. For the finished products part there should be the possibility for us to add new products. The Client can choose the color and size of the cloth and that's it. The customize design part will be a bit more complex. At first the client is choosing the product from a photo. It should be possible to add new products. The second Part will be the design. You can see a graphic of a shirt or jacket (don't need to look like the real product). An Outline of the shirt would be OK too. Than there should be three categories: Embroidery, Heat Transfer film and Print. The Admin should have the possibility to block one of these categories if it is not suitable for the products. Because embroidery designs cannot be resized easily it is not necessary that the client can scale the designs inside the Configurator. We will give fixed sizes of the designs and he can choose between one or two different sizes. It would be nice if he can place the design freely on the shirt but if this is too complex for the budget it would be enough if the client can choose between middle chest, chest right and chest left or on the back. After he has chosen the Design he can add text. The category Print has additionally the possibility to upload your own Design. So I think that should give you a roundabout idea of what we would like to have. Please be honest with the budged you need for the project and if you have other ideas how to do this web shop within the budged don't hesitate to send us a detailed description of how you would do it. I added a picture how the grafic of a product could look like...