thanks for such a detailed comment and for the nice words! To adress your feedback:
1. Yeah, scrolling varies so much with devices and I only had my MacBook to test on, so on windows devices it could be widely different
2. This was actually intentional to entice you to “save up” before the next level up, but given that multiple people have complained i should have probably done it differently
3. Upgrading is something that was originally a much larger aspect of the game design. I was going to make the buildings have a specific capacity for the max number of customers inside of them and upgrading would increase this capacity. In the end i didn’t manage to implement that due to time constraints and just made the upgrades give you some xp and boost all future sales in that building