He is trying to flip it into a profit. Although it would be much faster if he just grinded out on /jobs if he wants to create a town anytime soon.
It also depends on the diamond market, but if you do sell them higher than what you bought them for then you will make a profit (well, maybe not a big profit since diamonds are dirt cheap now)
Also, who are you buying diamonds from and where can I meet this person who is selling them for $100 each??
~ @SX1
Classified information sir, but every time I go to sleep I wake up with under $100 balance from people selling diamonds to me at $190 a piece. I know one other person who sells for $188 but still I can easily crack a profit from that.
Also I have other shops (wood ect) that I buy but the turn around is more than 4x the price I'm buying for sonit pays off. Plus you can only sell as much as the chest holds so there is some balance.
Wait why are you buying diamonds when you are saving for a town??
~ @Natsu
Just for fun, honestly buying for so cheap I'll make a profit reguardless. And, making a town is not a #1 priority as of right now. Just a future endeavor.