I've played this before, so let me pass a few quick game tips.
1. If you want to farm money as quick as possible, work at construction site and buy a fishing rod to catch the fish for fisherman points. The fisherman are the onle one who sell all the drill.
You can use all the drill at the same time, so but it all.
2. Every stamina recovery are numbered, so no need to upgrade max stamina early, instead buy the foods to recover stamina for better time plan management.
3. There is a secret on the construction site at midnight time.
PS: Try to lose to Rika, later she doing something that even man can't do XD.