You guys are wasting your time.
Delivering email to the inbox is far more complicated than those that tell you that you just need your own server want you to know.
I've been mailing for over 16 years.
You have to warm the IPs up and build up the IP reputation and you are not going to do it with free data (which is probably poor) that someone gave you. You send poor data and the IPs will just be blocked / blacklisted. So it is highly unlikely that you will ever turn a profit.
You can clean the data of bounces / threats, but this costs money. But even then you can't stop users from complaining and if you get too many spam complaints you are still toast.
There are ways to mitigate complaints, but it is completely impossible for anyone just starting out.
Anyway, just my 2 cents.