One thing to consider which im sure many of you haven't, what if the exchange gets hacked and a lot of funds go missing?
All those that join the group buy could be joint liable for the missing funds.
Wouldn't be the first or last time its happened.
1) You're not liable
2) Raise enough funds for a security audit of the code, and servers. As well as a crowdcurity campaign.
We actually already did all of that, we've also run an active crowdcurity campaign and payed a few hundred USD in bounties.