Not every store needs professional development, and I'd rather tell you upfront than take your money for something you could handle yourself.
You're launching a straightforward product catalogue. Fewer than 50 products, no custom functionality needed, and you're reasonably comfortable with technology? A premium OS 2.0 theme (Dawn, Refresh, Craft) will get you 80% of the way there. Shopify's setup wizard has gotten genuinely good. Spend the savings on product photography instead.
Your total budget is under $3,000. At that level, a developer is going to cut corners somewhere, and you won't like where. You'll get more value from a $350 premium theme, a Shopify plan, and putting the remaining $2,000 into content and marketing. Come back to us when the store is generating revenue and you have a specific problem to solve.
Your brief is a screenshot of a competitor's store. If the entire specification is "make it look like this," you don't need a developer. You need a theme that's close enough and a few hours of customisation. Be honest about whether you're paying for functionality or aesthetics, because the price tags are very different.
Your real problem is traffic, not technology. A gorgeous store with no visitors is still an empty store. If your current site works fine but nobody is finding it, your budget is better spent on content, SEO, or targeted advertising before anyone touches the codebase.