Hi,
In HikaShop you can use the characteristics in order to have many dropdowns with different values on the product page.
Then in the product edition page, you can click on manage variants to set different prices depending on the configurations.
Another way could be to use the options, but it seems to be less adapted in your case.
Here is some documentation about the characteristics:
hikashop.com/support/support/documentati...html#characteristics
Regarding the file uploader, you have to use the custom fields and select Ajax upload.