I don't think you need anymore than the free tier of Amazon AWS, which is extremely cheap. You can easily get a Windows server with 2GB RAM for $0.014/hr, which amounts to just about $10 per month, and provides you with the ability to host a server anywhere in the world. Amazon is also super reliable. It's not automatic, but it does allow for a lot of configuration options;' Setup will take some time, but you can pretty easily get it done. There is also a free tier which allows for 1gb of RAM. I don't recommend it for any more than a small world with about 5 players, but it's still an option.