Research functionality and price.
Usually, you need to add a huge part of functionality and tools to a marketplace long after it starts working.
That's why you should define which tools and features you'll need when the number of items, customers, and sellers' expectations will increase. Then compare cms different prices and functionality in that context.
Free solutions will enable only limited functionality, which needs to be expanded soon, and often, it'll cost much more than the initial package of a chargeable cms.
Heather Noss, a seller from Etsy, is a good example
of how you can lose the best vendor due to a limited multi vendor ecommerce platform functionality.
She opened a shop on the marketplace, but due to her business growth, she needed tools that weren't present at the shopping mall. She set up another channel, and now, 80 percent of her revenue comes to her directly, and only 20 percent—through Etsy.
Thus, a good move is to make some investments upfront, to save on the long-run and get a quality ecommerce solution intended to satisfy all the needs of your sellers.
From the other hand, you shouldn't pay just for a well-established brand.
The best way to avoid that is by running a trial period
. Find multi store platforms that offer full functionality during a free trial period, try it yourself and make an informed conclusion.