MVP Baseball 2004 Cheats

This can give you an awesome player easily.  While on Dynasty
mode create a player.  Make the player really bad.  Then you can
sign him for dirt cheap!  Then go to edit player.  Then put his
rating all the way up.  You will have an awesome player for a
few years, and only pay him a few hundred dollars a week.
(pitchers, shortstops are the most effective defensively)  

The following bonuses can be unlocked with the indicated number of MVP points:
Stadiums

First make sure that you are home. Next get into the bottom of the ninth with a tie. Then get your second baseman to replace the pitcher (that has been pitching for the entire game) have the second baseman up next. The guy that is up now needs to get a homerun. And the second baseman will get the save. You will see this after you quit the game!

In Dynasty Mode you recieve MVP points periodically for accomplishments. Assemble a team you feel is good enough to simulate to the playoffs (hint: Yankees). Simulate the season up to the second to last game and then save the game. Once you have it saved, simulate the last game and move into the playoffs. Generally, you recieve anywhere between 5000-9000 MVP points for making the playoffs. Save the points onto your profile when prompted, and then exit the Dynasty mode without saving. Repeat the process and you'll notice that every time you simulate into the playoffs you're saving the points and not your progress. Do this about 20-25 times and you'll have enough points for all the rewards.