Hey Marketplace Founders, what helped you grow your startup?

As much as I love marketplaces, I wished someone told me how hard it is to build them. Almost two years in and I'm just now starting to get a hold of our supply-side down. I'm building MeaningfulWork (https://www.meaningful.ca/) after I saw how many nonprofits struggled to find help during the pandemic while people wanted to give back in ways in however they were capable of. After using an Airtable sheet for a hot few months we transitioned into actually developing a web app. Would love it if you had any resources or some growth hacking tips around marketplaces. p.s. Glad I created a PH account today, seems like a great community here and soon I can also do a launch here. A little nervous thinking about it, looking forward to putting some time in!