The issue with having your own server and getting blacklisted is because (like myself), people do not usually set a PTR for reverse DNS so that the emails comes from your domain name and not the IP address. 

It's also wise to monitor Spamhaus to make sure you are not blacklisted there. A TON of websites use that to determine if you are a spammer or not. It's pretty simple to get unblocked from there once you get everything setup on your server. 

I couldn't even post my website on Twitter because I was blacklisted at Spamhaus and not to mention, MailChimp also suspended my account for this. Once I submitted to be removed, everything went well.