Add lot option: Online and app users, start time must begin at current time.
When this option is selected, daily parkers who scan the QR code or pay by app cannot select a start time, the start time begins when they pay. This is to encourage customers to find a parking space fist before they pay for parking so they know that they can get a space.
If a customer pays for parking ahead of time and there are no spaces available when they get there, they are going to be calling for a refund, even if we say "No Refunds" before the checkout page.
This option could be lot specific so you can turn it on or off in each lot depending on circumstance.
After a user selects the lot, there could be a place to make a note. ex: Must park vehicle in lot before renting a space, No-Refunds. Space is not guaranteed if you leave for any reason.