Mad Eddy's and the Beta Shop
Go to town.
Press and hold, all at the same time: F12, R, N, and Q.
hit 'Cancel' to go back to your house.
When you go back to town, there should be two new shops: Mad Eddy's and the Beta Shop.
Mad Eddy gives you free money, and lets you buy very rare items, among other things.
The Beta Shop lets you select the ENDing, among other things.
you can look at this page for usefull tips
http://princessmaker.maison-otaku.net/princess.htm
for basic instruction..........
http://www.kkpmc.net/pm2/pm2.htm