Edit Products on shopify create bundles

Looking for somebody who's is very familiar and efficient with Shopify and Apps. We have a bathing suit line that we are trying to get inventory uploaded. Our main goal is to download an App that will allow us to to sell diff size tops and bottoms of a bathing suit set. Our website will allow a customer to choose a top and bottom size but our inventory gets a little screwed up by doing this. Need it simplified, we have been on numerous phone conversations with Shopify and have downloaded countless apps. We are seeking somebody specialized in this line of work!