Shopify website for a pharmacy

I need the total overhaul of a Shopify website which I set up: https://harpers-pharmacy.myshopify.com/, including moving to a new URL.

We mainly sell on Amazon and eBay, and want to move our inventory to our Shopify store.

We want our inventory organised via into "OTC Medication", "Nutrition", "Wound dressings & other medical appliances", "Testing strips & other reagents.

We have not given a fixed budget, choosing a per hour arrangement, as any fixed budget proposed by us may not be realistic.