Picking a development partner is mostly about reducing risk. The code matters, but so does whether the team communicates, documents, and hands over something you own.
Ask to see shipped work that is live right now — not screenshots. Ask who owns the code and the accounts (it should be you). Ask what stack they use and why; modern, mainstream choices like React, Node and Flutter mean you can hire someone else later if you need to.
Ask how they handle changes and support after launch, and get it in writing. Ask for a fixed scope and a fixed price for the first phase. Ask how they approach Arabic and RTL if that matters to your audience. And ask about SEO — a beautiful site that no one can find is a poster, not a tool.
Codrex answers all seven the same way every time, and our portfolio is all live links. That is the standard to hold any team to.