I got some question and suggestion.
Have you use extension ? You create the extension by your own or what extension you use?
When you making this game, are you using the City Builder gdevelop example game? Or create your own?(the example too confusedXD)
Are your programming mostly using coding?
I not manage to make like when you build a house then your money will deducted.
You can change the t ime to days, season, year.Make the time slower. Can make festival acctivity according to the season.
The music can change randomly according to the season, time.
Anyway, Hope you can make improvement and win in next Gdevelop game jam!