The cheapest that I've found, almost like a light-weight Mailchimp, is EmailOctopus ( https://yourlink.to/email-octopus ) with a cost of $19pm for 10k subscribers. At this level of subscribers, you could also check out Mailchimp ($75pm), Campaign Monitor ($89pm), MailerLite ($35pm) or Get Response ($65pm). Hope this helps.

I created a free resource site for finding Wordpress marketplace themes at https://marketplacethemes.com . I hope this helps.

Check out this free site for tips on growing a two-sided marketplace - https://www.sharetribe.com/academy/

I'd recommend that you check out https://leandomainsearch.com for names. Perhaps look at two-word .com names or even look at purchasing industry-specific names with newer domain extensions like builder.io or builder.to then offering these directly to builders etc

One left-of-centre strategy I've seen is to have employees document one of their work procedures each day in a central, online SOP. Make it really simple & fast to add the procedure. Next, run a small competition where employees can, with a positive bent, add suggestions for ways that procedures can be streamlined. Have the winner be the person who provides the most, positive, useful feedback that benefits the company.

This does depend on the marketplace but generally advertising works for both supply and demand whilst it is a good strategy to limit your marketplace in some way (i.e. geographically) so you can ensure adequate supply to meet growing demand. I hope this helps.

Challenges that I've seen include: - having orders placed but not fulfilled - having vendors work around the payment process - having shopping cart/marketplace software that handles shopping carts + shipping fees from various locations A few other hurdles but worth the challenge :)

Have you had a look into Intercom, Drift or Help Scout Beacons? I hope these help.

If you're looking for something simple, check out the Journeys app on iOS ( https://www.youtube.com/watch?v=uUgzxeJnmkk ) or check out https://www.smaply.com/ or https://uxpressia.com/#cjm

My one tip would be to read the book, Buzzing Communities. I'd been looking at ways to develop my marketplaces and social networks and the information was gold!