Create advanced booking forms

If I want to create a form to – for example – manage hotel bookings or manage hairdresser's appointments, I need the form to:

1) Allow two-way communicate with a database (e.g. Google Sheets is fine for starters) to see if the selected dates or timeframes are available (and if so, the price of those dates or timeframes).

2) Have advanced conditional logic to dynamically recommend rooms or room combinations based on the number of guests for hotels (or at least: have conditional logic in place to make sure they're not overbooking – which still means enhancing your conditional logic values).

3) Have the option to open a small gallery and/or text field directly below each individual checkbox item automatically (when checkbox is checked) or manually, to provide more information about what they're booking.

Now, hotels and hairdressers might seem too specific at first. But these fundamental features would actually be incredibly useful in a wide range of other use-cases too.