Making bundle APP on Shopify

Background: We are Slick Case, a mid-size Hong Kong eccomerce for almost 2 years, [login to view URL] . We are very instagram & facebook savy. Work Goal: We are looking for Shopify expert for solving our Shopify inventory problem: [login to view URL] We have product bundling as the link above which one package include 3 individual products. When one package was sold. Shopify system of course don’t decrease each individual product inventory number. And the original system can’t count the minimal number of each individual product as the inventory number of that package product. It also can’t increase back the individual product number if someone refund the package. We tried a Shopify APP called Bundles ([login to view URL]). But its GUI is not suitable if there are so many product bundling. We want a Shopify APP have convenient GUI like importing a csv file with the SKUs of PACKAGE and EACH individual product. Than it can arrange Shopify system to count the inventory as above description automatically. The budget is not "$30-250", which we will discuss together.