Game loop:

• Buy store
• Buy bikes
• Order bike parts
• Receive bikes
• Rent bikes
• Repair bikes
• Sell old bikes
• Expand store
• Hire staff
• Assign staff to different roles
• Buy more bikes
• Rent more bikes
• Buy new store

each of these aspects of the game loop should be games themselves.

Buying bikes you should compare different models and requirements Weight and size