FYI, he only gives you four props in all. They're Santa themed, a beard, a gift box, a Santa hat, and a bag. The rest you have to earn by performing in musicals and are given to you by random people in the entrance hall after your performance.
The musical theater owner gives you a few special ones when you talk to him after certain situations. He is on the upper floor.
- Crown prop when you talk to him after you win first place in a musical 5 times(maybe just one, I forgot)
- Winner's Belt after you win first place 30 times
- Tiara when you play with another real person. Talk to the lady to the left behind the counter to connect to someone. How you perform doesn't matter.
- Birthday Cake when you talk to him on your Birthday. I don't recommend you change the date on your DS to match your birthday, but rather change your birthday to match the date on your DS. That's what worked for me.
Hope this helped! I've had my gold trainer card for a few days now. :3 Just need to get those streaks in the Subway now...