AAARRRGGGHHH! Not another one!
Think for a second, please!
SONY have a team of ooh, at least 50+ people working on Everquest 2, pay bucket loads of cash for servers etc. (I saw an estimate in PC Gamer that a MMORPG takes anything around £2-3million in development)
And you want to create a MMORPG in your bedroom/office????
Good luck!
If you really can model every single item in your world yourself (or get your friends to help) and develop the game code, and balance the stats/gameplay, and develop a database system to hold the ever changing world info and work out how to set up the multiplayer element then YES, you can make a MMORPG! It'll just take you from now 'til the day you die.
"You get what everyone gets, you get a lifetime!" - Death, The Sandman Library
First you Dream, then you ... - Neil Gaiman, 2001