We currently run an existing B2B services business, so have theoretically built up both sides of a 'marketplace' over 8 years. And now were thinking about changing our business model to a marketplace model. Given that's in place and we can see marketplaces in closely related markets operating, how much validation should we do?
Validation is really important when starting any tech project. However it's also imperative that you stay lean where possible.
The short answer without knowing the fine details about your project, I would suggest that the best way to validate your idea is to somehow create a low cost and lean MVP of your product idea (preferably without spending huge amounts of money on web or software dev). Then bring a small sample of your user base onto said platform to perform beta testing. I'd choose past clients that have loyalty to your brand and are willing to give feedback.
The long answer is that this is something that we would usually workshop. We have created frameworks for various situations, including launching a new tech product, where we guide our clients through the various different types of validation, from conceptual to ideas for a lean beta. For us its really important to get to know the project before jumping in and giving specific advice.
You can find some info on our workshops here: https://www.devwiz.com.au/build-your-idea-workshop/
Also if you want some tips on how to validate your idea in house, you can check out this article: https://www.devwiz.com.au/2019/09/04/validating-your-app-idea/
If you want some more specific advice, please feel free to book a call back through our website.
Cheers and good luck!