Disclaimer: I write down my business ideas that I can implement in a day or in the worst case less than a week. The principle is to figure out something simple but still useful. I may do or not do them in the future but I write them down to offload them from my head to make space for other ideas.
Idea: tool for professionals to allow their clients to schedule time.
Hire: professionals like beauty salons and etc.
Price: free and paid for extra features (like sms reminders)
Direct Competitors: there are many expensive tools doing this.
Indirect Competitors: doing it manually.
Why I think I can do it fast: it is quite simple project.