If you are interested in MMO and using Blitz, I might suggest Realm Crafter.
The RC1 uses Blitz3D for client and BlitzPlus for the server, will offer sources to the client and server and the game editor and might be what you are looking for if you want to have something affordable to start with.
The RC1 uses Blitz3D for client and BlitzPlus for the server, will offer sources to the client and server and the game editor and might be what you are looking for if you want to have something affordable to start with.