While in my first season in Div 4:
12000
2000
500
27
This will help get you out of Div 4 when you start building a team to win Div 4.
I am leaving Div 4 with:
13100
2500
500
40
You only need 27 boxes until you are ready to promote to Div 3. During the season I added more lower. I upped my bleachers and luxury during the playoffs.
I am glad you are thinking arena first. This will help you buy the players you need to support a title run in Div 4.