I have a business idea, how to build a product in the most efficient way without hiring a technical team?
The most efficient way without hiring a technical team is to find a technical co-founder. And where do you find them...? well, CoFoundersLab is a good place to start. Look for hands on techies with 10+ years of experience, these guys know their stuff.
I started Kriya.ai to solve this exact problem by aligning the top freelancers to help founders build their ideas into MVPs.
I am curious to know if there are any other solutions that others here follow?
You can hire a development firm to help you build a POC or a MVP for your product which you can then use to seek funding or otherwise launch. There are many development agencies in just about any country with varying levels of skill and expertise.
You might want to try to pitch your idea to more than one such firm and get a technical proposal. Comparing those would give you more information.
Outsourcing your initial work doesn't mean you won't end up hiring your own technical team. It will give you a way to move forward without deep commitments.